DannyDuberstein said:
I always chalked this up to Empire Ego. It's a little like Jerry Jones firing Jimmy Johnson and spending the past 20+ years trying to do it himself. I do think it bothered Lucas that Empire became widely known as the superior movie of the original trilogy and that many chalked it up to the fact it wasn't written or directed by Lucas. So he was going to have his hands all over the new trilogy in every way.
Having watched all of the special edition documentary / segments, I also wonder if he got so frustrated by the technology that he was stuck with in the OT that he gave up being dictator on the OT. When we got the special editions & the prequels, he grabbed the reins because he could create what he wanted now. And boy, did that suck or what!