There is also the interesting case of people with multiple areas of expertise. This is an understudied phenomenon, but I think it can shed light on the issue.

There is also the interesting case of people with multiple areas of expertise. This is an understudied phenomenon, but I think it can shed light on the issue. There are some skills that just come more easily to a person, and this is demonstrated by the case where you have the same person doing very similar things for similar lengths of time but in one case they become legitimately expert and in another they get better, but fall well short of true expertise. I'm a brilliant poet (if I do say so myself) but while I've invested at least as much time in prose I know I'll never be as good. This doesn't mean practice isn't important, but it does mean that talent matters, both for how fast you improve and the ultimate capability you reach.