You should know that Erik ten Hag was successful in his first season at Manchester United, because Erik ten Hag managed to make Manchester United finish in third place in his first season. Therefore, even if, for example, Erik ten Hag was at Chelsea and was successful like that in his first season, then of course Chelsea would not sack him either.
Chelsea is not like Manchester United, the owners don't give second chance and they're not relenting when the appointed coach in charge looks incompetent. Todd Boehly sack Mauricio Pochettino and was bad news for the Blues because Mauricio Pochettino have sealed the europa spot but couldn't convert his chances. Manchester United hooked up with Erik Ten Hag because he was the man for the job. He deliver quite exceptional tasks for the growth of the Red Devils. Erik Ten Hag would have been successful in Chelsea.
Chelsea is not having a great day after roman was leaving from EPL. The fundamental issue is that the coach with a different philo would always be sacked by the owner and this is happening with some of chelsea players. The moment Chelsea fired Pochettino proved it. Considering that Chelsea was not doing so well the previous season and todd once again did the wrong thing, there was a rather poor choice made by the Blues owner like recruit amateur coach to handle the big club that has spent a half of billions last season just to rebuild the club.
Pochettino proved to the world that he was capable, but the owner was not even giving him a chance. Roman, on the other hand was always substituting a world-class coach for another. It's a very different period now. Todd is just bringing chelsea to the low standard with his owning style.
This is obviously another setback for chelsea following how todd was once again repeat the same mistake like when he recruited potter as a new coach.
Things have not been going so well for the club.
Tod replaced Pochettino with an amateur coach. It's really inappropriate decision from him.