Current boss Jose Mourinho has suggested that the club’s progress stalled since the retirement of Alex Ferguson, Moyes’s successor, but the Scot is having none of it.
“Jose has his opinion, but there was always going to be a transitional period after Sir Alex’s time was over,” Moyes told the Daily Mirror.
“There was a changing of the guard. Not only did I replace Alex, David Gill had also stepped down as chief executive and Ed Woodward came in.
“So it was always going to take time. Yes, I took over the champions, but clubs like Chelsea and Manchester City spent huge amounts of that money that summer in a bid to overtake us. And it was difficult for me to go into Old Trafford and rip up the team that had just ran away with the title.
“I have no regrets about taking the United job. When you get offered a job like that, you take it. When you compare my season to what Jose achieved last season, it is about those small margins.
“United were always going to have to go through a difficult time when Alex left. You only have to see how much money they have spent over the last three years just to build a team capable of challenging for the title again to see how difficult the job was.”