Every team makes mistakes and until when those mistakes are done that they realized somethings cannot be undone again. They made a big mistake sacking Nagelsmann and he rejected another offer from them to manage the team again. Signing Tuchel at the time that Nagelsmann was sacked was not a wrong choice to me, but sacking Tuchel again after just few seasons even after reaching the semifinals of the Champions League was wrong and now Kompany is here again.
I hope Kompany don’t face the same fate as them because it has now become very obvious that it is not just about how their performance is, they end up getting sacked by the end of the day, maybe after making one or two mistakes and end up getting a result beyond their expectations. Kompany should try but if he gets sacked after few years without him wanting to leave by himself, he’ll still be considered as a failed coach in the team without minding the good times they’ve spent together.
I agree that firing Nagelsmann was a mistake, I think they realized this later, but everyone makes mistakes, without it you won’t be able to learn and grow. Negelsman refused for the reason that he was involved in the German national team, otherwise I think he would have returned with pleasure. We cannot know whether Bayern made a mistake regarding Kompany because it is too early to draw any conclusions. I think that in any case he will have one season to show what he is capable of, Bayern is a team with huge opportunities, and it may be easier to achieve success here than with weaker teams.
The reason why they sacked him was because Bayern Munich wasn't playing up to the expectations of the club board and the necessary steps they feel to tackle the issue was to actually sack him as a manager because if it comes to player, I think Bayern Munich already have all it takes when it comes to players to actually make things work so firing him and employing kompany is the next step, now it's just left for it to actually work out.