Amorim is having the same problem that Ten Hag had in United because he left his shit for Amorim to clean and that has become a pain on Amorim ass. Amorim hasn't spent a full season in United and he hasn't been able to buy the players of his choice for us to see if he can manage the club or not. Overhaul of those players will be good and put United in a better position to replace these players signed by Amorim. However, Leverkusen is not Manchester United and Ten Hag will have a different fate over there.
This is exactly why Amorim need more time than given to prove himself. Ten Hag left a lot of mess to be cleaned up, starting from the players psychology to their form, and even technical approaches to the tactical arrangements to every game, bringing back the team spirit amongst the players and building a better coach and players relationship to enable a conducive environment for the players to thrive are all the bulk of Work Amorim has got to put up with for him to be able to get the team back on track and producing the kind of results expected of them.