Unfortunately in sports it is your record that dictates how good of a coach you are. It does not really matter the ability of your players. It goes to can you form and shape them into a championship team. Andre Villas-Boas could not do just that and should have been let go sooner. He might be able to do it somewhere else but Tottenham was not the right fit for this team.
Yes, since he messed up pretty good, and a lot of people think that he can not do his job all that good, he should have been fired in the middle of the season so that they could get someone in there that is very good and can do better.
I do not believe former Tottenham Hotspur manager Andre Villas-Boas should have been fired mid-season. I believe this can create a huge problem for the teams as shifts in management often lead to changes in coaching and in the player line up. I think it is best to handle these things in the off season.
That was such a harsh decision to sack AVB. They had sold Bale to Real Madrid and spent all 100 million pounds on basically a whole new squad. They brought in a lot of world class players and there was no way they could be expected to gel and play as a team in half a season. He should have been allowed to see the season out at least.
I believe the situation with Andre - Villas - Boas was handled correctly you can't take someone out of a leadership role in the middle of a season because you have that individual you look up to to run that area of you life and if you take that away it could ruin any motivation that you have to do well.