I think the question is "Why did it take Powe so long to learn how to rotate, and where he was supposed to be on offense?"
I know some of you refuse to accept this, but in his first year and a half (and even for a while after he started getting playing time), Powe looked like he was playing in a different system than anyone else. He could go get the ball, but he had no clue where to be, and gummed up everything else.