He gets caught out when other people fuck up. That's his inexperience. For the Southampton goal, Sané was not where he was supposed to be so he couldn't pass to him. Kompany was in an awful position, then realised and moved just as Stones was passing. Kompany had never played in a back 3 before and clearly wasn't comfortable with it. It's not arrogance to assume the player you're playing with is going to be where he's supposed to be. Christ if Barcelona players got slated for not looking at the recipient every time they passed they'd be fucking nowhere. Only people desperate to pursue an "arrogant" angle (which has always followed the CB who dares to play with the ball at feet) would accuse him of that over something each player on the pitch does multiple times per game.
The other thing he needs is to bulk up a bit, which will come with age and time in the gym, so he can keep on doing things like fending off Costa while the ball goes out of play.