There are different ways of measuring success. If you want to call topping the charts success, then OK, Rufus doesn't really have it. But if we look at the quality of the music, Rufus will be remembered as an important contributor to music. Beyonce, on the other hand...not so much.
Rufus is a talented composer of modern day art music. His first two albums (self-titled and Poses) explore a wide variety of styles (mostly in the folk/alt genres). His next two albums, Want One and Want Two, show a more mature Rufus. In particular, Rufus' orchestrations in "Agnus Dei" are breath-taking. "The Art Teacher" and "Memphis Skyline" are also much more harmonically interesting than much of pop music today.
The amount of progress made through Rufus' latest album, "Release the Stars", is a testament to his place as an artist. From the politically charged "Going to a Town", to the chamber setting of "Nobody's Off the Hook", the gay-anthem "Between My Legs", the almost impressionistic "Leaving for Paris No. 2", and again, the beautifully orchestrated "Release the Stars", Rufus continues to show that he doesn't need to rely on the generic pop-formulas so prevalent in today's music. He draws on the history of western music and infuses his own style into his music.