From an IMDB article talking about George Lucas, on Star Wars Episode VI: Revenge of the Sith and an upcoming Vanity Fair photo spread featuring the stars of all six films:
"Lucas admits the final part of the opening trilogy marks the end of an era in his career - and he now plans to stop making successful films. He says, "I'm going to make movies nobody wants to see. I've earned the right to fail."
I think I'll just leave that one alone, thanks.