I did not say that Manchester United does not sack their head coach when they are not producing the results they are paid for but they give them time to see enough reason for sacking them. If Erick Ten Hag was Chelsea's head coach by now he could have been sacked by Chelsea. I see Manchester United giving Erick Ten Hag till January to buy some quality players that will help him fix the problems in Manchester United's squad, but if he fails to turn things around in Manchester United after the January transfer window, I think Manchester United has no choice but to sack he.
Erick Ten Hag should be able to take advantage of the time that Manchester United has given him at this time before the Manchester United team fires him for quite logical reasons. Because in the transfer window all teams will probably move to get great players to make the team stronger, so Manchester United also needs to provide more funds for this if they still want to hunt for great players for their own team. So Erick Ten Hag must be able to take advantage of the current moment for the good of his career at Manchester United.