Motivation crowding theory, also known as the crowding-out effect or the overjustification effect, is a psychological theory that suggests external incentives such as rewards or punishments can undermine intrinsic motivation. Proposed by psychologists Edward Deci and Richard Ryan, motivation crowding theory posits that when individuals are offered external rewards for engaging in activities they intrinsically enjoy, it can reduce their intrinsic motivation for those activities.

Key concepts of motivation crowding theory include:

1. Intrinsic Motivation: Intrinsic motivation refers to engaging in an activity for its inherent satisfaction or enjoyment. Individuals engage in intrinsically motivated activities because they find them interesting, enjoyable, or personally meaningful. Examples include pursuing hobbies, engaging in creative endeavors, or participating in activities that align with personal values and interests.
2. Extrinsic Rewards: Extrinsic rewards refer to external incentives or consequences offered to individuals for engaging in a particular behavior. These rewards can include tangible rewards such as money, prizes, or praise, as well as social rewards such as approval, recognition, or status. Extrinsic rewards are used to motivate individuals to perform certain tasks or behaviors.
3. Motivation Crowding Effect: The motivation crowding effect occurs when the introduction of extrinsic rewards undermines individuals’ intrinsic motivation for an activity. According to motivation crowding theory, when individuals are offered external rewards for activities they already find intrinsically rewarding, it can lead to a shift in their motivation orientation. Instead of engaging in the activity for its own sake, individuals may begin to view it as a means to obtain the external reward. This can reduce their enjoyment, interest, or commitment to the activity over time.
4. Undermining Intrinsic Motivation: Motivation crowding theory suggests several mechanisms through which extrinsic rewards can undermine intrinsic motivation:
   • Overjustification: When individuals receive extrinsic rewards for activities they already find intrinsically rewarding, they may come to perceive the external rewards as the main reason for engaging in the activity. This can diminish their intrinsic motivation by overshadowing the inherent enjoyment or satisfaction derived from the activity itself.
   • Loss of Autonomy: External rewards can also undermine individuals’ sense of autonomy and control over their behavior. When individuals feel coerced or pressured to engage in an activity for external rewards, it can decrease their intrinsic motivation by reducing their sense of choice and self-determination.
   • Shift in Focus: Extrinsic rewards can shift individuals’ focus away from the intrinsic aspects of the activity (e.g., enjoyment, mastery) toward external outcomes (e.g., rewards, recognition). This can lead individuals to prioritize extrinsic goals over intrinsic goals, thereby reducing their intrinsic motivation.
5. Implications for Practice: Motivation crowding theory has important implications for various domains, including education, work, and parenting. It suggests that relying too heavily on extrinsic rewards to motivate behavior can have unintended consequences, including a reduction in individuals’ intrinsic motivation and long-term engagement in the activity. Instead, practitioners should focus on fostering intrinsic motivation by supporting individuals’ autonomy, competence, and relatedness, and creating environments that promote intrinsic enjoyment and satisfaction in activities.