Curiosity is one of my major low-level motivators. For example, when debugging, it helps me to consciously refocus from “Let’s get X done. Obviously, it’s not done yet.” to “I’ve programmed it to do X. How come it does Y instead?” One could say that it boosts productivity just because it is a better-specified goal; but it feels like curiosity working.
Curiosity is also one of my major drives behind procrastination; the other is “getting (irrelevant) things done”.
I recently read David Goggins “Can’t Hurt Me”. On one level it does glorify superhuman pain tolerance. But a constructive perspective on such attitudes is: they illustrate courage. Do not tolerate pain, laugh at it! Do not tense under cold shower, relax into it. Do not bear problems, solve them.