A default is a quiet author of millions of apparently individual decisions.

Whatever is preselected becomes what most people end up with, not because they agree but because changing it requires a decision they never make. Millions of apparently individual choices turn out to be one person’s choice, made once, at the point where the default was set.

Where you have influence over defaults, treat setting them as a serious act rather than an implementation detail. And in your own life, notice that a good default beats willpower. Arranging your surroundings so the better option is the automatic one does more than deciding to be more disciplined.