You don't just give any old manager time. Doing that to a manager that isn't good enough is a 100% guarantee of failure, far more than changing managers is. And it's incredibly clear that all of our previous managers were not good enough, so utilising them in an argument to say that sacking them didn't work so we shouldn't sack any further managers is a terrible argument. The decision to keep ETH has to be based on ETH himself, not some imaginary scenario where if we'd kept Moyes/LVG/Mourinho/Ole they would have turned things around and we'd be successful which is effectively what you are doing.
If INEOS (or to be more exact the people they hire to make those decisions) judge that ETH isn't good enough, it'd be utterly idiotic to keep him just because sacking previous incompetent managers didn't work.
No, I think you don't get my point, I never said none of those managers should be sacked, they deserved to be sacked.
The way we operate, Ten Hag, his successor and so on will suffer the same fate.
Look back from LVG, Jose, they didnt get backed. Your response will say "they got £x million" so they got backed. However; that is not backing, spending useless money isnt backing. Jose wanted Martial and Shaw out, got Alexis half way through for fun.
Ole wanted Rice, Haaland, Jude, Grealish, Sancho, yes he got Sancho but he also got Diallo, Donny, Cavani, Ighalo instead.
Ten Hag wanted McTominay, Maguire gone and wanted a FDJ type player, got Casemiro, Weghorst, Sabitzer and Evans on loan.
Whilst he got Antony and others, you cant expect any manager to mix and match.
Look at the times they got those players as well, end of the window, so the manager has no pre season to integrate them.