I think the main factor for Manchester United is the team coach. Erik Ten Hag, who showed unsuccessful management, is still with the team. Chelsea, on the other hand, dismissed Pochettino from the team despite his outstanding performance at the end of the year. I think Manchester United has more stamina towards the coach. I think if he leaves the team, United is a team that can have more successful matches with a better coach.
With Manchester United I have always been of the idea that the coach has got a major part of the blame to bear because most obviously he's attitude towards the management of the team has been of a very great impact on the team they ahs caused the team the level at which they are currently. For Chelsea I'm still believing they know best why they go their coach who was beaming hope of revival for them.