Some of this has to be pride. Like, he is so confident in his system that he doesn't want to make changes unless he ABSOLUTELY has to.
His system works. We are undefeated and have taken 8 points from 4 fixtures that we got 0 points from last season. Hugo is having almost nothing to do in most of the matches.
Conte will always put the solidity of the team ahead of any other consideration. If making a change compromises the solidity of the team then he will not do it unless there is no other choice. That is why when games are tight he does not turn to players that he trusts less than his starting players.
What we need to work on now is improving our play with the ball without compromising the solidity of the team. As Conte has said many times, the team needs to play with personality. When the opponent just lets us have the ball (I believe we had like 70%+ in the first half) we have to do more than we did last night. At the very least push up and play in the opposing half.
We seem to have much more intensity when we are defending than when attacking, this is something Conte has to fix. If they are willing to bust a gut to make blocks and recovery runs then surely they should be just as willing to take the ball up the pitch and score?