I'm not sure either. Villa defended well. Other teams don't defend as well, so end product doesn't look like a desperate requirement.
The problem in that game is that Skrtel and Agger don't react well to players that they can't knock off the ball, like Benteke. They just back up and back up and give room to shoot from right outside the box, and we almost never have a final man between the shooter and GK.
Full credit to Villa though Benteke was a good buy and he's got a good future ahead of him. He's already much better than Darren Bent.