Not too sure with these assessments....Moyes not given enough time or full backing, Van Gaal = serial winner everywhere he went, employed to steady the ship, was defensive-minded, also not given enough time either (he naturally moves on quickly between jobs), bloodied plenty of youngsters.
Mourinho came off a bad Chelsea season, was and always will be a serial winner, not given enough time or transfer control.
Solskjaer = had the Man Utd blueprint but tactically woeful, too 'early' in the job (like Fat Frank The P.E Teacher) and unable to control the dressing room or drop out-of-form players *cough* Maguire *cough*
Sad part is that United have had the right managers at the club already and discarded them all (bar Ole and his magic wheel of course)
I bet Tuchel didn't dick around when taking over at Chelsea and didn't submit to the whims of the board, neither Conte at Spurs. The Glaziers pretty much marked the end of an era, unfortunately