Overjustification Effect: What it is and What it Shows About Motivation

A kid who draws on every napkin, receipt, and cereal box gets handed a shiny certificate for her artwork. Three weeks later the crayons sit untouched, and her parents are baffled. She wasn’t punished; she was rewarded. Something about the prize rearranged the meaning of the activity, so that drawing stopped being a thing she loved and became a thing she did for the sticker. Adults live this too: the hobby that turns joyless the moment it becomes a side hustle, the book club that gets tedious once there’s a reading quota.

Psychologists call this pattern the overjustification effect: when an external reward is added to something you already enjoy, your intrinsic motivation can shrink. It’s one of the most quoted findings in motivation research, and one of the most misquoted. Social media will tell you “rewards ruin everything.” The data say something more careful, and more useful.

So which is it?

Sometimes yes, sometimes no, and the conditions matter enormously.

This article explains the overjustification effect, the classic experiments behind it, the debate over its size, and what it shows about motivation at school, at work, and at home.

What is the overjustification effect, in plain terms?

The overjustification effect is a drop in intrinsic motivation that can occur after someone is given an expected external reward for doing an activity they already found enjoyable. People end up with more justification than they need, hence the name, and they start to attribute their effort to the reward instead of their own interest.

Two terms matter here. Intrinsic motivation means doing something because it’s interesting, satisfying, or meaningful in itself. Extrinsic motivation means doing it for a separate outcome: money, grades, praise, avoiding trouble. Neither is bad. Most real life is a blend, and nobody is purely driven by joy at an invoice.

The effect isn’t a claim that rewards never work. They often do work, especially for boring tasks nobody loves. The overjustification claim is narrower: for an activity you already like, a reward can change your own story about why you’re doing it.

Picture a pickup basketball game among coworkers on Thursday evenings. It’s loose, fun, a little chaotic. Then management announces a points system with prizes for the league’s top scorers. Within a month, people start arguing over fouls, skipping games they might lose, and checking the leaderboard instead of enjoying the run. The game hasn’t changed. The reason for playing has.

Three ingredients usually show up in demonstrations of the effect:

• The activity was already enjoyable before any reward appeared.
• The reward was expected, offered in advance as a condition of doing the task.
• The reward was tangible or controlling, such as cash, a prize, or a certificate, rather than information about how well the person was doing.

Notice what’s missing from that list: “any reward at all.” If the prize arrives as a surprise, or if it’s feedback that tells you you’re getting better, the picture changes. We’ll get to that.

The effect is also measured after the fact. Researchers typically watch what people do once the rewards are gone, in a free-choice period when nobody’s paying or praising. If time spent on the activity drops below that of an unrewarded group, the reward has done something odd. It bought the behavior while it lasted, and may have cost some of the appetite for it afterward.

That “afterward” is the real drama.

What happened in the famous Magic Marker study?

Preschoolers who expected a prize for drawing later drew about half as much on their own. That’s the headline from the best-known experiment on the topic, published in 1973 by Mark R. Lepper, David Greene, and Richard E. Nisbett, and it still anchors most textbook explanations.

Here’s how it worked. The researchers chose nursery-school children who already liked drawing with felt-tip “magic marker” pens during free play, confirmed by observers watching through a one-way mirror. Then they split the children into three groups.

1. Expected award: kids were shown a “Good Player” certificate with a ribbon and told they’d get it if they drew.
2. Unexpected award: kids drew without knowing about a prize, then got the same certificate as a surprise.
3. No award: kids drew and received nothing extra.

A week or two later, observers quietly recorded how much free time the children spent with the markers. The expected-award group showed significantly less interest than either of the other two. The kids who got an identical certificate as a surprise were fine, which tells you the damage wasn’t caused by the certificate itself. It was caused by working for it.

Imagine four-year-old Mei (an illustrative composite) who’s absorbed in coloring a purple elephant. A teacher says, “If you draw, you’ll get a special award.” Mei draws, collects the ribbon, and next week picks the blocks instead. For her, markers were a toy; now they feel like a job that pays in ribbons.

Some caveats are in order. The sample was small, and the children were in a single preschool. The measure was time spent drawing during free play, which is a behavioral stand-in for interest, not a direct look inside a child’s head. The quality of the drawings, interestingly, was also rated lower in the expected-award group in the original paper, though the main finding concerned interest.

Later studies have mostly (not always) replicated the pattern. That’s the kind of statement you want from a careful editor: robust enough to take seriously, mixed enough to avoid slogans.

The study’s staying power comes from how clean its logic is. Same reward, same activity, different expectation, different outcome. Few experiments in social psychology isolate a cause so neatly, and fewer have changed how teachers and managers think about gold stars.

Did money really change how people feel about puzzles?

Two years before the marker study, a young psychologist named Edward L. Deci ran experiments on adults that planted the idea. His 1971 paper in the Journal of Personality and Social Psychology reported that paying people for an enjoyable task reduced their later interest in it.

Deci used a puzzle called Soma, a set of blocks you arrange into shapes, which college students tended to find fun. In one session, students solved puzzles without payment. In the next, some were paid a dollar per puzzle solved, while a control group wasn’t. Then came an eight-minute free-choice period, during which the experimenter left the room, supposedly to enter data, and the participants could do whatever they wanted, including work on the puzzles or read magazines.

The paid group spent less free time on the puzzles than the unpaid group. In another version of the experiment, verbal praise did the opposite: it tended to increase interest. So money seemed to undercut motivation while positive feedback seemed to boost it. That split would shape Deci’s later theory.

The puzzle study has a stubborn legacy. It helped establish that it’s not the reward’s size that matters most; it’s what the reward communicates. A dollar per puzzle says, “This is work and I’m hiring you.” Praise says, “You’re good at this.”

It’s easy to oversell, though. Participants were college students in a lab, the money was modest, and the free-choice measure captures a few minutes of behavior. A 2022 direct replication of Deci’s 1971 design, published in an applied behavior analysis context, shows that people are still testing whether the original pattern holds under tighter methods. That’s healthy science: classic results get re-examined, not enshrined.

A real-world echo helps. Think of a woman who has knitted for decades, then opens an online shop. Orders come in; deadlines loom; custom requests arrive. Within a year, she tells a friend she can’t remember the last time she knitted something for herself. Her skill went up and her enjoyment went down. Lab studies don’t capture her story, but they do capture its logic.

What Deci was really pointing to was control. When rewards feel like a leash, we respond like creatures on a leash.

Why does getting paid make the fun disappear?

Because people infer their own motives from their behavior. Social psychologist Daryl Bem proposed this in his self-perception theory (1972): when our internal cues are weak or ambiguous, we figure out our attitudes by watching what we do and the circumstances around it, much as an outside observer would.

Apply it to the puzzle or the markers. “I’m drawing and I’m being rewarded for drawing; therefore I must be drawing for the reward.” The reward becomes a sufficient explanation, and the earlier explanation (“I like this”) fades. That’s the “overjustification” part: too many reasons, with the external one winning.

A second explanation comes from Deci’s cognitive evaluation theory, later folded into self-determination theory. It argues that rewards have two aspects: an informational one (this tells me I’m competent) and a controlling one (this is pressuring me to behave a certain way). Intrinsic motivation falls when the controlling aspect dominates, since we lose the feeling of acting from our own choice, and rises when the informational aspect dominates.

Together these accounts predict some specific things:

• A surprise reward shouldn’t hurt, because it never became the reason for acting.
• Heavy-handed rewards (“do this and you’ll get that”) should hurt more than gentle recognition.
• Rewards on a task you already dislike shouldn’t hurt, since there’s no interest to undermine.
• Rewards that signal real skill should help, because they strengthen the sense of competence.

Most of these predictions have found support, though some are debated.

Consider Sam (an illustrative composite), who volunteers at a community garden each Saturday. The organizers start giving $10 gift cards to anyone who logs three shifts in a month. Sam doesn’t need the cash, but notices himself counting shifts, wondering whether a half-day “counts,” and feeling faintly resentful when he can’t make it. The spade is the same. The meaning isn’t.

It’s worth admitting what we can’t say. Self-perception is an explanation of a pattern, not something anyone has directly watched happening in the brain. Different mechanisms probably contribute, and the evidence for each is indirect. That uncertainty doesn’t weaken the effect; it just keeps us honest about the “why.”

Which brings up a practical question: if rewards can backfire, when don’t they?

Do all rewards backfire, or only some?

Only some. A large meta-analysis of 128 experiments, led by Edward L. Deci with Richard Koestner and Richard M. Ryan and published in Psychological Bulletin in 1999, found that tangible rewards tended to undermine intrinsic motivation, but only under certain conditions.

Specifically, rewards that were engagement-contingent (for doing the task), completion-contingent (for finishing it), or performance-contingent (for doing well) each reduced free-choice interest, with effect sizes of about d = -0.40, -0.36, and -0.28, respectively. Those are small to moderate effects in standard terms. Positive verbal feedback, on the other hand, tended to enhance intrinsic motivation.

The same review pinned down the “escape hatches.” Rewards didn’t undermine interest when they were unexpected or when they were given regardless of task engagement, as with a flat salary.

One more finding deserves attention. Effects on self-reported interest (what people say) were smaller than effects on free-choice behavior (what people actually do). So you might tell a researcher you still love the activity while quietly choosing something else when nobody’s watching.

Reward “type” in the real world is rarely clean, though. A bonus can feel controlling or generous depending on the culture of the place that hands it out. The same $50 gift card reads differently from a boss who micromanages than from one who trusts you.

So the sloppy slogan “rewards destroy motivation” is wrong, and the opposite slogan (“rewards always motivate”) is wrong too. The truth lives in the conditions.

Is the overjustification effect actually a myth?

Myth: it’s been debunked. Fact: it’s been contested, trimmed, and qualified, but it hasn’t disappeared. The debate is mostly about how big and how general the effect is.

The loudest critics were behaviorists. Judy Cameron and W. David Pierce published a meta-analysis in 1994 in the Review of Educational Research arguing that rewards generally don’t harm intrinsic motivation, and that negative effects appear only in narrow circumstances, mainly when expected tangible rewards are given simply for doing a task. Their conclusion was that the fear of rewards was overblown, and that using them in classrooms was mostly safe.

Deci’s team disagreed. They argued that Cameron and Pierce’s review lumped together different kinds of studies and measures in ways that blurred real effects. A comment published alongside the 1999 meta-analysis concluded that the Deci et al. and Tang and Hall reviews captured the literature more accurately than the Cameron and Pierce one, while also warning about the unthinking use of meta-analysis on theoretically complex research. Researchers are still divided in emphasis.

What both camps largely agree on is this:

• Expected, tangible, contingent rewards for interesting tasks carry a genuine risk of undermining later interest.
• Verbal praise and informational feedback usually don’t harm and often help.
• Effects tend to be modest in size, not catastrophic.
• Replications are mixed, with an approximately equal number reporting a failure to replicate in some reviews.

Another qualifier: many studies measure a few minutes of play after a short experiment. Whether the effect lasts months or years, and whether it generalizes to complex jobs with salaries and bonuses, is less well established. The evidence here is thinner than the pop-psychology version suggests.

There’s also a gap between the lab and life. Real people have mixed motives. An ER nurse is motivated by purpose, pay, pride, and the need to pay rent, all at once. Mixed motivation isn’t a contradiction; it’s the normal state.

So treat the overjustification effect like a good rule of thumb with exceptions, not a law of nature. Wise managers and parents don’t throw out rewards. They stop and ask what a given reward is telling someone about why they’re doing the thing.

Fair? Fair enough, I’d say.

How does self-determination theory explain it all?

Self-determination theory (SDT) says people have three basic psychological needs, autonomy, competence, and relatedness, and that motivation thrives when those needs are supported. It’s the broader framework that grew out of the overjustification research, developed chiefly by Richard M. Ryan and Edward Deci.

In a widely cited 2000 paper in American Psychologist, Ryan and Deci laid out the theory’s core claim: autonomy (feeling that you’re acting from your own choice), competence (feeling effective), and relatedness (feeling connected to others) are innate needs, and when contexts satisfy them, people show more persistence, creativity, and well-being. When contexts thwart them, motivation and wellness decline.

That framework turns the overjustification effect into a special case. A controlling reward chips away at autonomy: “I’m doing this because I’m being paid.” Competence-affirming feedback does the opposite: “I’m good at this.” Same reward, different psychological message.

SDT also expanded the story beyond a simple intrinsic-versus-extrinsic split. It describes a continuum of motivation. At one end is external regulation (doing it for rewards or to avoid punishment). Next comes introjected regulation (doing it to avoid guilt or protect self-worth). Then identified regulation (you value the goal), and integrated regulation (the goal fits your identity). At the far end is intrinsic motivation. Through a process called internalization, people can come to own initially external goals, such as a student who dislikes practicing scales but values becoming a musician.

That’s an important refinement. Extrinsic motivation isn’t a single poisonous thing. A teenager studying for exams because “I want to become a nurse” is extrinsically motivated in the technical sense, but she’s volitional and engaged. A teenager studying out of fear of a parent’s anger isn’t.

SDT research also finds that the interpersonal climate around a reward matters. Rewards given in an autonomy-supportive context (choices offered, rationale explained, pressure minimal) were less likely to undermine intrinsic motivation and sometimes enhanced it, while the same rewards in a controlling context undermined it.

A quick vignette: two managers announce the same quarterly bonus. One says, “Hit your numbers or you’re on notice.” The other says, “Here’s what we’re aiming for, and here’s how the bonus recognizes it; tell me what you need.” The numbers on the check are identical. The psychological experience isn’t even close.

One honest limit: SDT is a broad, influential theory, but it’s also been criticized for being hard to falsify in places and for being tested mostly in Western samples. Cross-cultural work suggests the needs matter widely, though how autonomy is experienced can vary.

Can rewards hurt creativity?

They can, particularly when the reward makes a person feel watched and judged. Research by Teresa Amabile led to what she calls the intrinsic motivation principle of creativity: people are most creative when motivated primarily by interest, enjoyment, and challenge, and not by external pressures.

Her book Creativity in Context summarizes decades of experiments in which participants made collages, wrote poems, or told stories under different conditions. When people expected evaluation or a contingent reward, their work was often judged as less creative by independent raters, compared with people who simply worked for fun. The effect wasn’t universal, but it showed up often enough to be taken seriously.

A subtler point is that Amabile also discussed “synergistic” extrinsic motivators: rewards that confirm competence or enable the work, such as extra resources, recognition of skill, or tools, can complement intrinsic drive. The problem isn’t extrinsic motivation per se. It’s extrinsic motivation that controls.

Consider Ravi (an illustrative composite), a designer at a small agency. When his boss says, “Surprise me, and take your time,” he produces strange, thoughtful concepts. When the same boss says, “The best idea gets the $500 bonus, and the client will pick,” he sketches safe options he thinks will win. The reward didn’t ruin his skill; it narrowed his willingness to take risks.

It makes sense. Creativity requires exploring, failing, and wandering off-topic, and a prize attached to a result pulls attention toward the target. In the lab, that sometimes produces more rigid thinking.

The finding has limits. It’s strongest for open-ended, heuristic tasks (those without a clear path) and weaker for algorithmic ones, where rewards can improve speed and accuracy. If you’re asked to enter data, a bonus may help. If you’re asked to invent a new product, a bonus may not.

So what should a creative team lead do? Offer meaningful goals, reduce evaluation anxiety, provide autonomy over how the work gets done, and leave out the “win this prize” contests unless the goal is a quick, safe output.

Does it change how kids behave toward others?

Possibly, and the evidence is intriguing but thinner. In a 2008 study, Felix Warneken and Michael Tomasello tested 20-month-old toddlers who spontaneously helped an adult, for example by picking up a dropped object. Some toddlers were then rewarded with a toy for helping, and later, when the rewards stopped, those children helped less often than children who had never been rewarded.

The authors interpreted the result as support for an overjustification-like process: toddlers’ helping seemed to be intrinsically motivated, and tangible rewards seemed to undermine it. Nobody should overgeneralize from a handful of experiments with toddlers in one lab, and researchers continue to examine how robust and widespread the finding is. But it’s a thought-provoking nudge about prosocial motivation.

Critics of reward-heavy parenting and schooling, most famously author Alfie Kohn in Punished by Rewards (1993), argue that sticker charts, grade-based incentives, and praise-based management teach children to work for payoffs and not for meaning. Kohn’s book is polemical, selectively drawn from the research and popular rather than strictly scientific, and some psychologists think it overstates the case. But it’s influenced debates about classrooms and parenting for decades.

Where does that leave an everyday parent? Probably with moderation and judgment, not a ban. Some practical considerations:

• Use rewards for tasks kids dislike (chores, practice drills), not for activities they already love, such as reading for fun.
• Prefer specific feedback (“you kept going when it got tricky”) over generic bribes.
• Give surprise treats to celebrate effort without making them a condition.
• Offer choices and explain reasons, so children feel like participants, not subjects.
• Avoid turning kindness into a transaction, such as paying for every sibling hug.

Take Dana (an illustrative composite), whose seven-year-old loved reading comics until a school program offered a pizza party for the most minutes logged. Soon she was reading shorter books with bigger pictures and watching the clock. The program raised minutes and cooled the love, which is a trade few teachers intend.

The evidence on schooling is mixed, to be fair; some incentive programs show benefits, particularly where children have little initial interest. Context decides.

How can you use rewards without killing motivation?

Match the reward to the situation. If the task is already interesting, minimize contingent tangible rewards and lean on feedback, autonomy, and meaning. If it’s dull but necessary, rewards are reasonable. And whatever you do, notice what your system tells people about why they’re doing the work.

Here’s a six-step approach that fits most workplaces, classrooms, and homes:

1. Diagnose the starting motivation. Is this activity something the person already enjoys? If yes, tread lightly with prizes and quotas.
2. Prefer informational feedback. Say what was good and why. “Your explanation made the problem easier to see” does more than “Great job!”
3. Use unexpected recognition. A surprise thank-you or celebration after the fact tends not to become the reason for acting.
4. Preserve choice. Let people decide how, when, or sometimes what. Even small choices support the sense of autonomy that SDT highlights.
5. Explain the point. For uninteresting tasks, give a real rationale. People accept boring work more readily when the purpose is clear.
6. Pay fairly, then stop dangling. A decent, predictable salary prevents resentment and, as the meta-analysis found, non-contingent pay doesn’t undermine interest in the work itself.

For self-motivation, apply the same ideas to yourself. If you love running, think twice before turning every run into a points-and-badges competition on an app. If you’ve begun to dread it, try a “no-tracking” week and see what returns. Conversely, if you hate doing taxes, a reward after finishing is a perfectly sane trick.

Watch for early warning signs that a reward system is backfiring:

• People ask what’s in it for them before agreeing to anything extra.
• Effort drops sharply when the incentive ends.
• The work becomes safer and more minimal, aimed at the target and nothing else.
• Enjoyment fades, and someone says “it used to be fun.”

None of this is a call to abolish pay, grades, or prizes. Society runs on them, and many people couldn’t pursue their interests without income. The practical wisdom is simpler: use rewards as tools, with an eye on the message they send.

What are you doing right now for love that you’ve turned into a scoreboard?

FAQs about the Overjustification Effect

What is the overjustification effect in simple words?

It’s what happens when a reward makes you care less about something you used to enjoy. You start with an interest in an activity, someone offers you a prize or payment for doing it, and afterward your own motivation drops. The idea is that you begin explaining your behavior by the reward (“I’m doing this for the prize”) instead of by your interest (“I like this”). It works best as a rule of thumb, not a law: it tends to occur with expected, tangible rewards for activities you already find interesting, and it doesn’t usually appear with surprise rewards or with feedback that tells you you’re doing well.

What is an example of the overjustification effect?

A classic case is the 1973 preschool study by Lepper, Greene, and Nisbett. Children who liked drawing with markers were promised a “Good Player” certificate for drawing. Later, in free play, they spent less time with the markers than children who drew without expecting anything or who received the certificate as a surprise. An everyday example is a hobbyist photographer who turns pro and soon stops taking pictures for fun. Another is a student who loved reading until a school program began awarding points for every page logged. The pattern is the same: the reward becomes the reason.

Does the overjustification effect apply to adults?

Yes, though the strength varies. Edward Deci’s early experiments used college students working on puzzles and found that paying them reduced later free-time interest in the task. Workplace research on self-determination theory has also linked controlling incentives to lower intrinsic motivation, while autonomy-supportive environments tend to protect it. Adults have more complicated motives than toddlers, including financial need, career goals, and professional pride, so the effect may be diluted in real jobs. A common adult version is the hobby that loses its charm once it turns into a paid side business.

Does praise cause the overjustification effect?

Generally not. In the 1999 meta-analysis of 128 experiments, positive verbal feedback tended to increase intrinsic motivation rather than undermine it. The caveat is that praise can feel controlling if it’s used to push particular behavior (“good girl for sitting quietly”) or if it’s vague and excessive. Specific, sincere feedback that signals competence, such as “that was a clever way to solve it,” tends to support motivation. Generic or manipulative praise can backfire a little, since people can sense when it’s being used as a lever.

Are bonuses at work bad for motivation?

Not necessarily. Fair, predictable pay doesn’t appear to undermine interest in the work, and the 1999 review found that rewards not tied to task engagement or given unexpectedly didn’t reduce intrinsic motivation. Trouble tends to come when bonuses are tightly contingent on narrow targets for work people already care about, particularly if the climate feels controlling. For routine, unglamorous tasks, incentives can improve performance without much risk. For creative or purpose-driven work, it’s wiser to combine fair pay with autonomy, feedback, and recognition after the fact.

Has the overjustification effect been disproven?

No. It’s been debated and refined. Reviews disagree about how large and widespread the effect is: Judy Cameron and David Pierce argued in 1994 that negative effects were limited, while Deci, Koestner, and Ryan’s 1999 meta-analysis found reliable undermining under specific conditions, with effect sizes in the small-to-moderate range. Some replication attempts have succeeded and others haven’t, and the effect appears sensitive to methods and context. The most defensible summary is that expected tangible rewards for interesting tasks can reduce later interest, often modestly, while many other kinds of rewards don’t.

How do I stop my kids from losing interest when I reward them?

Reserve rewards for tasks they find tedious, and avoid paying them for things they already love. Offer specific praise about effort and strategy, explain why a chore matters, and give choices where you can. Surprise celebrations after a milestone are less likely to turn the activity into a transaction than “do X and you’ll get Y” deals. If you’ve already set up a sticker chart and enthusiasm is sliding, try phasing it out gradually and replacing it with attention and conversation. Watch what happens when the reward disappears; that’s the best test of whether interest is still there.

Is the overjustification effect the same as the undermining effect?

Closely related, and often used interchangeably, but the terms come from slightly different traditions. Overjustification refers to the explanation proposed by Lepper and colleagues, that people have an excess of reasons for acting and credit the external one. Undermining is the broader descriptive term for any drop in intrinsic motivation due to external rewards, whatever the mechanism, including the loss of autonomy proposed in cognitive evaluation theory. Researchers sometimes say “undermining effect” to stay neutral about why it happens, since several mechanisms may be at work.

Bibliography

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• Bem, D. J. (1972). Self-perception theory. In L. Berkowitz (Ed.), Advances in experimental social psychology (Vol. 6, pp. 1-62). Academic Press.
• Cameron, J., & Pierce, W. D. (1994). Reinforcement, reward, and intrinsic motivation: A meta-analysis. Review of Educational Research, 64(3), 363-423.
• Deci, E. L. (1971). Effects of externally mediated rewards on intrinsic motivation. Journal of Personality and Social Psychology, 18(1), 105-115.
• Deci, E. L., Koestner, R., & Ryan, R. M. (1999). A meta-analytic review of experiments examining the effects of extrinsic rewards on intrinsic motivation. Psychological Bulletin, 125(6), 627-668.
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• Warneken, F., & Tomasello, M. (2008). Extrinsic rewards undermine altruistic tendencies in 20-month-olds. Developmental Psychology, 44(6), 1785-1788.