Why it was said

BJ Fogg writes this in the chapter on celebration, after two decades of behavior research at Stanford and a long argument with the folk wisdom that habits come from doing something for 21 or 66 days. His lab kept finding that a behavior wires in when it is followed by a positive feeling, and stays fragile when it is not, however often it is repeated.

What it actually means

Repetition is how you notice a habit has formed; it is not what forms it. What forms it is the brain tagging a behavior as worth repeating, and the tag is emotional. That is why a routine you dutifully repeat for a month can vanish the week you stop forcing it, while something that felt good once can stick immediately. The practical consequence is counterintuitive: the moment right after the behavior matters more than the behavior's size. A deliberate flash of satisfaction, what Fogg calls celebration, does more for a habit than adding another rep.

How to use it

1. 1Attach a real, immediate feeling of success to the end of the habit: a fist pump, a said-out-loud 'yes', a note of the win.
2. 2If a habit feels like a chore every time, shrink it until finishing it produces relief or pride, then grow it from there.
3. 3Stop counting streak days as the measure; count whether the habit felt good to finish today.