Overjustification

Rewards motivate—this is a fundamental assumption of incentive systems. Incentivizing customers with points, discounts, or rewards should increase their engagement. Yet companies often observe the opposite: after introducing rewards, intrinsic motivation declines, activities become mechanical, and enjoyment disappears. The question is: When do external incentives destroy internal motivation, which types of rewards are dangerous—and what does the evidence tell us?

Studies

The Drawing Experiment with Preschool Children

Mark Lepper, David Greene, and Richard Nisbett conducted a groundbreaking experiment at Stanford University in 1973 with 51 preschool children. The researchers selected children who enjoyed drawing—an activity with high intrinsic motivation. The children were divided into three groups: The first group was told in advance they would receive a "Good Player Award" certificate with a gold seal for drawing. The second group drew without prior announcement and unexpectedly received the same certificate at the end. The third group drew without any reward. Two weeks later, the researchers discreetly observed the children during free playtime. The result was striking: Children in the expected-reward group spent only half as much time drawing as before (9% versus 18% of playtime). The no-reward and surprise-reward groups showed no decrease. The announced reward had transformed drawing from a joyful activity into an obligation.

The SOMA Puzzle Experiment

In 1971, Edward Deci conducted a series of experiments at the University of Rochester that provided the first systematic demonstration of the overjustification effect. Twenty-four college students were asked to solve creative puzzles over three sessions—an intrinsically motivating task. Each session consisted of three phases: 13 minutes of puzzle-solving, an 8-minute break (during which participants were alone and observed), followed by another 5 minutes of puzzles. The experimental group received one dollar per solved puzzle in the second session, while the control group received no payment. The critical finding emerged in the third session when payment was withdrawn: the previously paid group spent significantly less time with the puzzles during the break (free time when they were unobserved) compared to the first session—their intrinsic motivation had declined. The control group showed no such change. The payment had transformed the activity from a pleasure into work.

Principle

Which principle for Customer Experience Design can be derived from this? The core principle is: Protect intrinsic motivation rather than overlaying it with rewards—autonomy and a sense of competence are stronger binding forces than points. For customer experience, this means that reward systems like loyalty points or cashback may work in the short term but can undermine the natural enjoyment of the brand or product in the long term. This becomes particularly critical when customers already have an emotional connection to the brand or use the product out of conviction—here, external incentives can weaken the authentic relationship. Instead, companies should focus on experiences that strengthen the sense of autonomy, competence, and meaningfulness, as these nourish intrinsic motivation rather than displacing it. The following guidelines show how to implement this principle concretely.

Guidelines

Reward only unattractive tasks

# CX Guideline: Only Reward Unattractive Tasks Use point systems and material incentives strategically for activities customers perceive as obligations—data updates, security settings, documentation. Activities customers already enjoy—using the product, consuming content, interacting with others—should NOT be additionally incentivized. Rewards would transform existing enjoyment into a transaction and reduce motivation over time.

Surprise with recognition

Replace predictable reward systems with unexpected, personalized gestures of appreciation. Instead of offering "points for every purchase," consider alternatives like sending a handwritten thank-you note after particularly engaged usage, providing an unannounced upgrade, or making a personal phone call. Unexpected recognition is perceived as a gift rather than payment—and it doesn't undermine intrinsic motivation. The timing and format should remain non-standardized.

Signal competence instead of payment

Design feedback mechanisms that make progress and mastery visible—skill levels, achievements, milestones, and competence badges. This form of recognition supports the experience of competence and strengthens intrinsic motivation rather than undermining it. Critical consideration: Badges should be genuinely difficult to achieve and represent real accomplishment. Inflationary "participation" badges (such as "you logged in") function like extrinsic rewards and destroy the intended effect.

Provide autonomy in reward systems

If a rewards program exists, design it to give customers maximum control: free choice of rewards, flexible redemption without expiration dates, and opt-in rather than automatic enrollment. When customers perceive the system as a tool they control themselves rather than as external control, the detrimental effect on intrinsic motivation is reduced. The key principle: the program should support autonomy, not restrict it.

Only reward new behaviors

Don't reward what customers do anyway. Loyalty programs should incentivize new, desired behavior – not turn existing purchase behavior into a transaction. The following examples illustrate this guideline:

• Starbucks Rewards: Points not just for purchases, but for challenges: 'Try a new drink this week', 'Order before 9 AM'. New behaviors are encouraged, not existing ones rewarded.
• Nike Run Club: Badges for new milestones, not for every activity. The reward reinforces achieving new goals, not continuing existing habits.

Surprising instead of expected rewards

Unexpected rewards avoid the overjustification effect. The customer cannot attribute their behavior to the reward because they did not anticipate it. The following examples illustrate this guideline:

• Zappos: Random upgrades to express shipping without announcement. The surprise strengthens the relationship without creating expectations.
• Hotels: Room upgrade upon arrival instead of announced in advance. The guest does not attribute their return to the upgrade – it remains a gift.

Recognition instead of material rewards

Competence feedback and recognition strengthen intrinsic motivation rather than undermining it. 'You're good at this' has a different effect than 'Here's your reward'. The following examples illustrate this guideline:

• Duolingo: Streak celebrations, achievement badges, leaderboards – recognition for progress, not material rewards. This preserves intrinsic motivation for learning.
• GitHub: Contribution graphs, achievements, public profiles. The visibility and recognition of work is what motivates – not money for commits.