Same for professional writers, or what have you, any creative work, really. Your brain needs calories for neurons to fire, and the more they fire the more connections they build associated with the pattern they had when firing... a.k.a. "The accumulation of ki"
It sucks when you're good at learning lessons the hard way, been handed the shit end of the stick in life, and have strengths
not apparent to untrained eyes, whereas most trained eyes are hostile at least to some extent... got to be resilient.