It is true that Manchester United always gives its coaches enough time, but I disagree with you if Manchester United's new coach fails to win 10 matches in a row, Manchester United won't sack the coach because that era is gone. If Ruben Amorim fails to win more matches for Manchester United when the international break is over, he will be at a big risk of losing his job at Manchester United.
Manchester United has been really linnet in recent times and with the case of Amorim I do no think it is time for them to take such drastic actions immediately but then I hope Amorim does not make everyone get weary of his poor results so far but then Manchester United will very much likely still give him some more time just like they did with Ten Hag, I know that Amorim is trying to get along with the team but it is actually taking too long.
Manchester United management hired Ruben Amorim to replace Erik Ten Hag because they want positive change, and they believe Ruben Amorim could perform better than Erik Ten Hag and improve Manchester United's performance, but with the way Ruben Amorim is currently performing at Manchester United shows that he can't handle the situation at Manchester United. The era where Manchester United management used to be patient with their coaches is gone. If Ruben Amorim doesn't perform better this month, Manchester United management might likely relieve him of his job.