#2 Failure to get the best out of his players
Jose Mourinho has infamously complained about the spending of his rivals and how he did not get the players he asked for during this transfer window, but beyond his grandstanding lies the fact that the 56-year-old has simply not gotten the best out of the bunch available to him.
Jose inherited a squad which was admittedly devoid of too much quality, but he still had some promisisng talents within the squad including Anthony Martial, Marcus Rashford and Luke Shaw, but it is hard to argue that any one of them has improved in almost three years of Mourinho's tutelage.
Beyond the players he inherited, Mourinho has made 11 signings as Manchester United boss, with most of them being sanctioned by him at a total cost of about £391m (which is second to only Manchester City's spend in the same time), but while Manchester City can justify their spending as they are unarguably the best club in the league, Manchester United are nowhere near being the second best team in England.
Mourinho might not admit it, but he had the privilege of working with the most expensive midfielder, the most expensive striker and the highest paid player in EPL history, but the squad looked nothing like that.
Alexis Sanchez and Fred are both players who were actively sought by Man City but they ended up at United and look nothing like the players they were at their previous clubs.
Paul Pogba, Romelu Lukaku, Henrikh Mkhitaryan (forgot for a moment he was ever a United player), Eric Bailly, Nemanja Matic, Diego Dalot, Zlatan Ibrahimovic, Victor Lindelof. These are the players signed by Jose Mourinho as Manchester United manager and they were all either highly rated or world class at their previous clubs, but other than one or two who have performed fairly, all the others dropped significantly, with Sanchez perhaps being the best (or worst) example.
At Manchester City, all of Pep's signings have gelled in well (apart from Nolito and Bravo who are arguably his only dud signings) even Mahrez has slotted in seamlessly, while he improved the likes of Raheem Sterling and Fabian Delph among others.
At Liverpool, the story is not much different as Klopp goes about building a solid team capable of pushing City all the way in their quest for a first league title in three decades.
Sarri has also scored impressively with his teransfers, while Tottenham infamously became the first side to not make a transfer signing.
Jose Mourinho has lamented a lot about the fact that he was not backed in the market, but the truth is that he had a lot of quality at his disposal and his failure to get the best out of them was to be his albatross.