Here's what usually happens as time goes on (and in order of frequency).

1)They keep on making the same song over and over again, with diminishing returns. (Half of all hip-hop mc's, Nickelback, etc).

2)They flip the scrip totally, not realizing that while in their lane they are Dale Earnhart JR, but in that other lane they are sunday drivers getting lapped. (See any third album by a popular rock band. If they are mega popular, they pull this the second album).

3)They get more insular in their world. (Lots of IDM artists)