This is where each of us is unique mix - I couldn't care about improvement in things I do for fun. If it comes naturally, great, if it doesn't, same great. I know many people who aren't like that, especially competitive ones (which I consider a rather big disadvantage in life if one of your goals is to be a happy content person).

The only reasons I do it - to have fun and relax - is already there, it doesn't get better the better I get since there is not top level cap. One example - I do climbing, in & out. If I climb 4c (french grade, which is very beginner level), say after some accident or other longer time off, its the same type of challenge as climbing routes at 5c/6a level after some training period. It really doesn't change anything for me, the challenge, fear of fall/death, pushing through it and sense of accomplishment is the same.

Maybe not the best mental wiring to achieve most in life in measurable aspects like career or net worth, but sure as hell I can be happy with little. It is great. I wish more people were like this.