No, in fact these two examples and what you are saying perfectly illustrate my point - that is the English game is way too brutal and follow the "one strike, or sometimes two strikers, and you're out" type of managerial employment philosophy. Managers are given very little chance to perform and if they get sacked, it will leave a black mark on their CV. They don't get to make comebacks like Ancelotti, Allegri, and Luis Enrique. Ancelotti had rubbish last seasons at Parma and AC Milan, but was still employed by Juventus and Chelsea because the owners trusted his potential.
However, this does not seem to happen as often in England. No matter how much everyone hates David Moyes here, Moyes is a GOOD manager. He took over Everton from Preston North End when Everton was in a terrible shape and facing administration. He kept them in the Premier League, consistently got them to mid-table and sometimes to a European position, and helped Everton become a longstanding Premier League force they are today for Koeman and Martinez. However, after failing at United, no club even wants to employ him now. His decade of achievement at Everton was erased by just 10 months at United. I think he is too big for Sunderland, a club which is in serious mismanagement. Southampton and Watford did not even consider him when they were looking for a manager during the summer. You can't blame the man for being bitter about United when now he has to manage Sunderland. Sunderland isn't giving him transfer funds this January and he is losing players to AFCON. The position at Sunderland is similar to the one at Swansea - a poisoned chalice. There is a high chance that he will fail with Sunderland and everyone will go," See! I told you he is rubbish!" But his club is Sunderland! Moyes could have made a comeback if he were given a job at Southampton or Watford.