I believe Moyes was also good but his time with MU was very bad he spend some good time here in Everton but now Martinez is doing very good job but they still far away from champions league last season I was sure they can do but at the end Arsenal was better team at the end
He was just good in Everton, not great. And I really don't understand why did Sir Alex chose him. He didn't have any exceptional result and just average is not good enough for Manchester United.
Its happen many times great peoples done mistakes so this happen by Sir Alex and he chose a wrong person for his great team but I think now they have good person