no one is denying mirkos talents or contributions and assists. but you cannot deny having watched the season up to this point, there were instances when he could've done better by passing/crossing instead of holding on to the ball. he may not be a selfish player per se, as shown by his numerous assists, but this is a flaw in his game.
if I recall in the game vs Milan, at the end of the first half when we were 1-1, Vucinic had a massive opportunity to just pass the ball across to Giacc who was open (Vuci having plenty of space) for a tap-in, but instead opted to turn and turn and give a high cross which by then Milan defenders had come in. There was also one instance in the second half, while we were still 1-1, when Vuci could've crossed from the side with two Juve players in the box and near the keeper instead of shooting for an angled side netting.
I'm not criticizing our MoTM in his game in this coppa match, no one is but this is one of the reasons why people get frustrated with Mirko this season. In coppa it was only two opportunities, in his bad days it could be throughout a whole game.