This is thing that I saw repeatedly with WCS last year, and it has absolutely nothing with who he plays with or the fact that it's a young team learning defense. He didn't sprint back on defense. It drove me freaking crazy seeing the purported speed demon of big man being so lackadaisical getting back on defense. To me, it's like a control experiment where you eliminate all other variables in order to see the one remaining variable - effort - and find that is very wanting. I just can't tolerate that. I could really get behind him, despite all his other faults, if he would show effort. But he repeatedly proved to me that he was more interested in conserving his energy than in expending his energy. Now it may be that WCS is just one of those guys who doesn't have stamina and will never have the stamina for the NBA game and that's the best that he can do. But the end result is the same - a fast player with no motor.