As someone who has been professionally engaged in goal setting and habit building for 7 years (and personally interested for much longer), something that keeps annoying me is the way so many apps seem to try to motivate people using streaks... When in reality, streaks only work for some kinds of habits, and some kinds of goals, and once a streak is broken, your motivation is, too. Streaks are fragile and there's a much better way to think about your goals and habits.