Yeah and that will be one of the reasons why his performances for Juve were better than they have been here (amongst many reasons like).
But as a young striker if you're coming off the bench when your team is winning comfortably there's little to no pressure on you and you can go and express yourself.
Thats very different to coming on in a tight game when you're expected to either make the difference if were chasing the game, or not do anything stupid (ie giving the ball away cheaply) if were winning.
IMO he looks like he suffers from that, when he comes on he tries too hard and doesn't relax and play his game. His better performances have come when hes started (Salford aside)