External rewards may seem effective, but often reduce long-term intrinsic motivation. External motivators like grades or rewards can boost short-term engagement. However, they can undermine intrinsic motivation over time. Students may become dependent on rewards and lose interest in learning for its own sake. This is the “Motivation Illusion.” Example: Students receive stickers or bonus points for good work. Once the rewards stop, their motivation drops — they were used to external triggers instead of internal interest.
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.
Ryan, R. M., & Deci, E. L. (2000). Intrinsic and extrinsic motivations: Classic definitions and new directions. Contemporary Educational Psychology, 25(1), 54–67.
Lepper, M. R., Greene, D., & Nisbett, R. E. (1973). Undermining children’s intrinsic interest with extrinsic reward: A test of the “overjustification” hypothesis. Journal of Personality and Social Psychology, 28(1), 129–137.