You're comparing managers who have managed the biggest clubs in the country, with some of the biggest budgets in the world, to Sam Allardyce who has managed some of the smallest clubs in the country. Hardly a fair comparison.
No one can transform a club though in 4 and a half months, well some people might get lucky when all the right ingredients were already there that compliment their style, but it often doesn't last long.
What I would say though, is Allardyce is actually very similar to Mourinho, he just needs a break, and with a good preseason, and a few additions I think he's gonna surprise a few of you (if he stays). I think by hounding Big Sam out though, you might be missing out on an untapped gem who just needs an opportunity at a big club with a decent budget.
Allardyce has left every single one of his clubs in a better league position than when he joined. That is some record considering how many clubs he has managed. An astute tactician, good record in the transfer market, innovative behind the scenes, good motivator, wealth of experience, you're turning your nose up at someone who is pretty good at what he does!