Artists and Improvement

In response to Mary's post question. " My question right now is what is an artist to do once they have reached the peak of their performance and can no longer improve?"
I think that artists can never really reach that point where there is no room for improvement. There are so many different art styles and emotions to experiment with and perfect that it is impossible to perfect them all in the short period of time we have to live. If an artist truly reaches the peak of their performance then they will probably make a lot of money. There are exceptions to that obviously if a person is handicapped and cannot improve then, because society would most likely be understanding towards that individual, but otherwise people are genetically designed to adapt and improve.
Question: What do you think?