Jose Mourinho has admitted his players must "learn to survive" with the expectation that comes with playing for Manchester United.
The United manager shocked the media with a 12-minute monologue at his Friday news conference - asking supporters for patience as he attempts to rebuild the club's "football heritage", following Tuesday's Champions League exit.
Mourinho continued to stress that the club is in a restructuring process, explaining defeats such as that to Sevilla will teach the squad how to deal with the burden of being a United player.
"They have to learn how to cope with that level of expectation and that level of pressure and they have to survive and when they survive they become stronger," Mourinho said.
"You know, easy life, and the fans not upset and no critics, that's not good.That's not good, because if you want to make a real top team with top mentality they need to grow up.
"They need to grow up and the best way to grow up is to have this kind of feeling. So, I don't want the fans to have lower expectations, I want the fans to have high expectations because I want the players to have high expectations too."
Mourinho was full of praise for the long-term planning of Manchester City, and suggested United would struggle to challenge the runaway league leaders next season if they continue to develop and invest in their squad.
"If the clubs that are in a better situation than us, if they stop to invest, in everything and we do invest, I would say, we are side to side," Mourinho said, ahead of United's FA Cup quarter-final tie against Brighton.
"But if they are in a better situation than us, and they keep investing the same or more than us, it's difficult. It's difficult. It's as simple as that. It's difficult."
When asked if they will challenge for the Premier League next season, he said: "We try, but the reality is that some clubs, they were ready to win [this season]. They were ready to win and other clubs are not ready to win.
"To develop a process is one thing, to go for the jugular is another thing."