#3 His man-management has been quite poor
One of the main reasons why the Special One has been so successful in his career has been his ability to manage players. Wherever he has gone to, Mourinho has been able to get players to buy in completely into his vision and this has translated into trophies and glory.
With hindsight, it has become clear that his time at Real Madrid led to the antsy, always-annoyed Mourinho of today. Before turning up at the Santiago Bernabeu, he had coached players and teams who had been going through a prolonged dry spell and hadn’t done much in their careers (FC Porto, his first stint at Chelsea and his time at Inter Milan). These players were in awe of his abilities and record and were willing to run through walls for him.
At Madrid, he met a dressing room filled with players who had won Euros, World Cups, multiple league titles and Champions Leagues. He was unable to adapt his methods and this led to lots of friction in the dressing room.
At United, his fallouts with players like Paul Pogba, Martial, and Shaw among others have seen these players underperform. His inability to coax consistently good performances from his players has been baffling and his “us-against-the-world” philosophy is one that looks to be at odds with the abilities/mentality of his Manchester United team.