There's some players who will always have excuses made for them.
They come from specific leagues where a specific system catered to their strengths.
One thing about United, our greatest weakness imo, we don't know how to let things go.
Chelsea, City and Liverpool have had lots of poor signings over the almost ten years we have been struggling to get back on top.
However, unlike United, once they realize how poor those players are, they don't give them many chances to redeem themselves. They take their losses and sell/loan the player. They get a transfer fee or get them off their wages partially and move on to sign a worthy player for their squad.
United and its fans however sign players and look for any signs of quality in the player, regardless of how many poor performances they have ( this includes young players too). Rashford and Martial literally both played consistently in 2017 and 2018 despite barely having any good performances. Yet when Mourinho signed Sanchez, instead of being happy about getting in a quality player ( at least what we thought at the time), some of our fans were more worries about how Rashford/Martial would develop. No other big club thinks like that. If you're good enough, you're old enough...not if you are young, you'll get an automatic opportunity. Arsenal made the same mistake with Diaby's Wilshere's and Traore's of this world. Getting sentimental, not signing players when these players were injured, in hope that they could give a potential chance to a young player they bought.
Fergie never did this. The only time he did anything close to that was with Forlan, as Forlan was performing, but was not scoring goals. Giggs was an instant performer, but he also had Kanchelskis and Lee Sharpe down the flanks in case. Beckham had to perform consistently to stay in the team. Scholes did not become a proper starting player until 97/98. Rooney was already a superstar that had proven himself before we signed him. Ronaldo was not an automatic starter when he came into the team. Since Fergie left, in trying to emulate his teams, we've almost been dogmatic in giving opportunities to young players and transfers that show an inkling of talent. Just like any company, Fergie identified the level of talent the player had once they reached his squad, and played them accordingly. Players like Park, Brown, Silvestre, Sheringham were at one point signed to be first team players, they proved not to be for the majority of time they were here ( Sheringham had the good 2001 season), so they became squad players. Players like Djemba-Djemba, Bellion, Poborsky etc who proved not be United quality were move on quickly.