He cut his own throat by texting Costa he was no longer wanted. I suspect that was when he lost the support of the players.
The change in his touchline behaviour, when celebrating or lack off, goals was also a giveaway all was not well.
As already mentioned, he kept moaning about the club’s transfer policy, but also refused to change the way he set the team up, constantly playing out of form players, in the same system. Heavy defeats against bottom half of the table teams, ultimately missing out on the CL, gave the club no option but to get rid of.
I shed no tears for him. To me he appears to have brought this upon himself.
So we move on to the next chapter.