A habit only survives difficulty if the person enjoys it, which makes enjoyment a better predictor of persistence than discipline.

Because if it's not fun, if it's not engaging or interesting, if it doesn't feel good, you're not going to stick with it when it gets tough. I mean, this is probably one of the great lessons for life, which is if you're having fun, then then you're dangerous, right? Then you're hard to compete with. You don't want to you don't want to go up against the person who's having a good time doing it because if it feels like a hassle or a chore, that's the person who gives up when it gets difficult.