Prolonged, high-intensity pursuit of goals can deplete dopamine and reduce motivation.

“if you were to pursue a goal, really, really go forward-center of mass for many, many hours or many, many days, in some cases, and pursue a goal or multiple goals and you're really driven to do a ton, what you're effectively doing is generating waves in that wave pool. And if those waves are too big, well, then the waves can't keep repeating themselves.”