I read somewhere that Neil Peart started taking drum lessons again. This would have been sometime in the last 10 years. You know, after Neil had already enjoyed a good 25-year run in Rush, and being largely regarded as one of the best drummers ever.
I took a lot of music lessons as a teenager (on alto sax), and I became decent. Did well in some jazz competitions, won some local awards, nothing big. But the driving force behind my efforts was "there's always someone better". If you think you've reached the top, and you stop trying to improve, then game over. You stagnate.
This would apply to any craft, wouldn't it?