The Greatest Rock Star?

Musing on Kanye West saying he is the greatest rock star: Just who is the greatest rock star ever? My vote would go to Iggy Pop. Being the "greatest" has nothing to do with record sales or money. It has to do with influence, musical risk taking and musical growth. Iggy has done all three. Plus he is in the Rock and Roll Hall of Fame (not Kanye). Ok, granted not many know who he is, and what he does isn't everyone's cup of tea, but we have to keep in mind the criteria here. It is "rock star" not music in general. The standard is in a very limited category. People may not like his music (which is fine) but he has done much in the narrow rock genre. Iggy is to hard rock and punk what Horowitz is to classical piano. He is a true master. Kanye could learn some things from him.