Possibly because...

it's hard to tell how much of a team's success/failure is actually down to the manager?
How many of the people on here praising Farke to the rafters were less than a year ago wanting him sacked because we weren't winning enough or scoring enough goals. Those things were true, but maybe that wasn't because Farke was a crap manager. There are loads of other factors involved.
Ditto Lambert. Loads of people now taking the piss out of him now were professing him some sort of messiah 8 years ago.
In football (and many other sports, but especially football because the margins by which most games are decided is so small) you can do the same thing with the same principles and get totally different results. Good managers can get bad results and vice versa.
Managers often get sacked not because they're actually to blame but because boards feel pressured to take action in a bad spell and changing a manager is much easier than changing a squad of players (especially outside a transfer window)

Posted By: mr carra, Apr 1, 12:55:05