If you look at the goals he has scored for Swansea and for us, you will see that he likes to pull the trigger on the ball as it is played to him.
That can lead to some cracking goals if you are the dominant team but that style coupled with his lack of movement and poor positional sense in my view reveal a very limited player who will never be an effective striker. Injuries just make that worse as he doesn't play regularly enough and has never shown any improvement.
The lack of application to try and create space or to try to stretch the opposition to open space up for other players is the biggest disappointment for me. He is going down the Jack Rodwell path if he doesn't have the desire to or just can't understand what he needs to do to develop as a striker.