When people notice habits or behaviors that they don’t want—eating too much, not exercising, not getting enough sleep, being inconsiderate—they usually start by using willpower to force themselves to change. When this fails, they often condemn themselves for being weak or a bad person. The author insists that such methods don’t address the basic principle that people do things that reward them.

Many systems of behavior management use punishment as part of the incentive system. Penalties work to some degree, but it’s a weak method and quickly collapses when the punishment disappears: “People change best by feeling good, not by feeling bad” (123).

A much stronger method is designing behaviors that reward a person for doing them. These new habits quickly become robust because they are reinforced in pleasing ways. The behavior itself, and not some outside agent, creates the reward.

One of the most powerful rewards is the feeling of self-worth that people get when they accomplish something. However, “[w]e rarely recognize our successes and feel good about what we’ve done” (130). The Tiny Habits system inserts rewards into new habits by celebrating every time the person performs the habit. The method uses self-praise. A quick, small gesture—saying "Awesome!", pumping a fist, even a simple smile—serves to induce a rewarding sense of self-approval.