Exactly.
On pitch results are what ultimately build a reputation.
If you have a good reputation, as a manager, you will have a lot more sway with the fans and your employers.
For the record, I think Moyes is 100% correct in what ever he has said so far (and this is coming from a MUFC fan who was dead against Moyes, from the get-go - I was desperate to see him gone).
How is he right in saying that he was wrongly dismissed from United job if you reckon that he should have been sacked?
He's not supposed to be telling the press that his players are too crap to be doing anything other than barely surviving relegation at best, either, even if it's true. He's the manager and he absolves himself of any blame in his first two weeks in the job by doing that.