This is just like the beginning of his career for United, it is his first full season he will take the club as the manager and the first transfer window he’s had. There is still enough time for him to work and try to get his team to shape. This season there are not much expectations for Amorim other than finishing in top 6 this season, any other achievement better than this will be a plus for Amorim, we can’t judge him just yet until his 2nd season at the club.
Manchester United need to consider the long-term future of a manager, and if he continues to sack players then it will be difficult to achieve success.
Amorim needs to be given ample opportunity to build this team into a more developed one. If he's fired too quickly for reasons of inability to deliver trophies, it will be difficult for any manager to make changes.
Manchester United's performance has improved slightly, and I think Amorim needs to lead the team to a top-five finish so that Manchester United can slowly emerge from the problems they've faced.
Not that Manchester United don't need long term consideration with coach, but it depends the agreement the coach entered with the team management that will make the management to give the opportunity to the coach, for team to see what he will help the team to achieve at the end of the season, once the management know that the coach will not make it with his promise with the management, then sack letter will follow to remove the coach without considering the short time the coach has spend in the team, i think Manchester United coach will help the team to perform well in this season because they displayed perfectly well in their first matc that make people to believe that Manchester United will reach top five in premier League table.