The worst bands and solo artists I've ever heard never really become popular.
However, if you want to talk about someone who gets played far more than I like it's Rick Astley. I remember that short time he was popular in the 80's. I thought, "Man this guy sucks, but soon people will get tired of him, and then I'll never have to hear his music again." Boy was I wrong.
Someone reply to this comment with a certain link. I've never seen someone asking for it more! Haha