He's very good at coming up with creative plots and good storytelling - but after a while it all seems generic and kind of the same - and he is not good (or doesn't bother enough as people buy it anyway) to avoid lots of plotholes in the stories and logic gaps. Or rather to bring the story lines together in the end, he seems to use ductape.

So I enjoyed his short stories much more, as they were much more consistent, than the big, blown up "masterworks" of him.