I definitely say YES with this. I meant replacing Motta with Xavi is very worthy decision for Juventus. I know some might be disagreed, but i personally think that if Motta is already failed in helping the club.
Juventus is not even a competitive compared to the Napoli and Intermilan, though they also spent a lot of money on summer last season.
If Juventus is willing to see its club to be back competitive again, they have to sign Xavi and sack Motta.
Currently for the option of changing coaches I will not answer YES, I want to give a chance first to see how far Motta brings Juventus and besides that currently Motta is gaining momentum in Serie A because slowly with his squad he is putting pressure on the 3 teams above them. I want to see them at the end of the season and where they are at that time. If Motta fails then I will agree to the change. My reason is simple, I see Fabregas has succeeded in improving the quality of the Como team's game. Xavi and Fabregas have almost the same playing style, if Fabregas is successful then Xavi can do it too, especially since Juventus has much better quality players.