If only changing the manager would put things right, I have my doubts.
Ole did bring some relief after the staleness of LvG and the negativity of Jose, he put a smile on all our faces, but alas he didn't tackle the really deep seated problems at the club and it was inevitable they would catch up with him. His inexperience under pressure told in the end, there appears to have been too many 'back stories' operating at the club, most of them resulting from the 'cocked up' lack of succession planning debacle, after Fergie left.
The worrying thing is who can sort out the crap? We have so called 'top players' seemingly not trying, or worse still they are not as 'top player material' as they think they are when they come under the massive pressure of wearing a United shirt, they cannot perform consistently, very few if any are real leaders, and the hierarchy in the playing staff is easy to spot, some players are on two or three times more money than their squad colleagues. In such cases and especially when the chips are down the tendency will be to tell the manager "get after him boss he's getting three times what we are and he's sh**e!
The training and coaching has been abysmal, for years really. Football is a simple game but you wouldn't think so watching United over recent seasons, attempts to incorporate modern influences coming into the game, e.g. like playing out from the back, putting on and sustaining a high press, pass and move shapes all over the pitch, are performed with amazing incompetence, that is repeated week after week, game after game, and every player involved seems scared to death when they get dragged into things.
Ole has made some changes, brought some decent players in, but all have eventually been sucked into the morass of incompetence, lack of confidence, etc. that seems to pervade all training/coaching right through to game planning. Hence his main failure has been seeming his inability to reverse these underlying problems. Whether he has been held back by the owners, or he has just failed to appreciate the problems, we shall have to wait for his 'My time at United' tell all book!
Undoubtedly the owners approach to running the club hasn't helped, but that's as much to do with a failure to 'clean house' as it is to making a profit. For the Owners there has to be a realization that the quick fix of going for star names ( worryingly more to sell shirts) hasn't worked, because whats broken needs more application and planning than that.
Good luck to Ole he has had a good go, but it was always a bridge too far in present circumstances.