Children who loved drawing were promised a certificate for doing it. Two weeks later, they drew 50% less during free play than kids who were never rewarded. The reward didn’t add to the fun. It replaced it (Lepper et al., 1973).
They stopped drawing the moment nobody was paying them to.
How Rewards Kill Motivation
This feels backwards. Rewards should increase motivation, right? More incentive, more effort?
For tasks you don’t enjoy, yes. Pay someone to do something boring and they’ll do more of it.
But for tasks you already enjoy, rewards do something destructive: they change why you do it.
Before the reward: “I draw because I love drawing.” During the reward: “I draw because I get a certificate.” After the reward is removed: “Why would I draw? There’s no certificate.”
Your brain recategorized the activity from intrinsic (I do this for me) to extrinsic (I do this for the reward). Remove the reward and there’s nothing left.
The Critical Distinction: Expected vs Surprise
Not all rewards are toxic. The Lepper study had three groups:
| Group | What happened | Drew during free play? |
|---|---|---|
| Expected reward | Told upfront they’d get a certificate | 50% less than before |
| Surprise reward | Got a certificate after, but didn’t know it was coming | Normal, no change |
| No reward | Just drew | Normal, no change |
Only the expected reward killed interest. The surprise reward was fine.
Why? Because expecting the reward shifts your reason for doing the activity. You start thinking: “I’m doing this for the certificate.” The surprise reward doesn’t shift anything because you didn’t know it was coming, so your brain never recategorized the activity.
It’s not the reward that kills motivation. It’s the expectation of it. The moment you think “I’m doing this to get something,” the activity stops being its own reward.
Where This Causes Real Damage
Paying Kids for Grades
Sounds logical: reward good grades, get better students.
The research says otherwise. Children who are paid for grades:
- Focus on easy courses that guarantee the reward, not challenging ones that promote growth
- Cheat more (the grade is the goal, not the learning)
- Show less interest in subjects after the payment program ends
- Develop a transactional view of education: “Why would I learn something if nobody’s paying me?”
The grade becomes the point, not the knowledge. Remove the payment and the curiosity goes with it.
Gamifying Work
Points, badges, leaderboards, streaks. Companies add game layers to make work “fun.”
It works in the short term. Then:
- The game becomes the focus, not the work itself
- People optimize for points, not for quality
- When the gamification is removed or becomes stale, motivation drops below where it started
- Employees who were once intrinsically interested now feel like they’re “working for points”
Praise That Backfires
Mueller & Dweck (1998) showed that the type of praise matters enormously:
| Praise type | What it says | Effect on motivation |
|---|---|---|
| Outcome praise | “You’re so smart!” | Shifts focus to external validation. Kids start avoiding challenges to protect the “smart” label. |
| Process praise | “You worked really hard!” | Keeps focus on effort and growth. Kids embrace challenges. |
Telling a child “you’re so smart” feels kind. But it creates a fragile motivation: “I need to keep proving I’m smart.” One failure threatens the identity. Process praise keeps the motivation internal: “Effort leads to growth.” Failure becomes information, not identity threat.
When Rewards Do Work
Rewards aren’t universally bad. They help when:
- The task is genuinely boring and has no intrinsic value. Paying someone to enter data into a spreadsheet isn’t going to kill their passion for data entry.
- The reward is unexpected. Surprise bonuses, spontaneous recognition, gifts that weren’t promised.
- The reward signals competence, not control. “Here’s a bonus because your work was outstanding” feels different from “here’s a bonus because you hit the target.”
- The reward comes with autonomy. “You earned this, spend it however you want” vs “here’s your reward for compliance.”
The question isn’t “should I reward?” It’s “will this reward change why they’re doing it?” If the answer is yes, the reward will cost more than it gives.