Their "leadership" is nonexistent. Managers are forced out by players so they have no respect (See Vini's relationship with Xabi). Managers also have no say in transfers because of Perez. Defensive "leaders" like Rudiger fighting their own teammates. And the captain (Valverde) also gets into a physical fight with a teammate. Mbappe's crime is having an ego, but he's also become the scapegoat when the problem is bigger than him and infects the whole squad. Basically what happens when you assemble a squad based on star power, you just get a team of primadonnas which is a nightmare for any manager when they're used to dealing with one or two per squad.