No. In fact, I'd say we gave Martinez six months more than he deserved. The second half of his second season was awful and the string of poor results, taken alongside his insistence on signing half the Wigan squad that he got relegated the year before, should have been seen as a clear indicator that things were amiss.
He got given the benefit of the doubt in the summer between his second and third seasons, probably due to misplaced notions that the results and performances in the first season were his "norm". However by the time we'd reached November in his third season Martinez had ripped the guts out of the defence Moyes had built and was telling anyone who would listen that Tom Cleverley and Aiden McGeady were CL- standard players. In retrospect he should have been booted out in the summer after his second season, but I'm amazed he didn't get the chop in December of his third season, giving a new man the January window to steady the ship.
Koeman certainly wasted more money than Martinez and accelerated the decline, but make no mistake: the rot started with Martinez. A manager who got Wigan relegated. If he was good enough to keep them up, then the players must have been cack and we shouldn't have signed them. But if the likes of Kone, Alcaraz and McCarthy were good enough to stay up then Martinez must have been inferior and we shouldn't have given him the keys to Finch Farm. Bill went all in, signing a relegated manager and giving him permission to sign half his relegated squad - utter stupidity, with utterly predictable results.