Wenger and Mourinho are both great managers. Would everyone be as comfortable with both just because they're 'great'? It doesn't work that way. A player moving to a new country, a new league has tonnes of things on his mind, not all of them football-related. It's vital for him to be able to rely upon the knowledge that the guy he works with everyday is in agreement about his thinking and development. I'm sure guys who've played football themselves will tell you that the relationship with the manager is the most important, even more so than his teammates. For the player it's important to have a great working relationship with the manager, not the board. At Chelsea, the manager doesn't set the club's direction, the owner's advisers do.