David Moyes has labeled his tenure at Manchester United as the greatest regret and failure of his managerial career.

Moyes took over from Sir Alex Ferguson in July 2013, following Ferguson’s retirement. Although Moyes began his stint with a Community Shield win against Wigan Athletic, this early success was a rare highlight in what turned out to be a troubled season.

Under Moyes' leadership, United experienced their worst-ever Premier League start, finishing in seventh place with 57 points from 34 games, well short of a Champions League spot. Moyes was dismissed in April 2014.

Reflecting on his time at Manchester United, Moyes admitted he still regrets not achieving more at the club. Speaking on William Hill’s "Up Front with Simon Jordan" (via Mirror), he said: “My time at Manchester United was a failure. If I have any regrets in my career, it's taking on one of the biggest jobs in world football and failing to make it work. That will always be my biggest regret when I retire.”

Moyes also shared the difficulties he faced, including the challenge of managing the fallout from his departure. He explained that he aimed to maintain Sir Alex Ferguson’s system and values, which he thought would suit him. Despite this, he faced criticism for his transfer dealings and management skills.

The 2013 summer transfer window was particularly frustrating for Moyes, with high-profile targets like Cesc Fàbregas, Thiago Alcântara, Gareth Bale, Cristiano Ronaldo, Leighton Baines, Luka Modric, and Ander Herrera failing to join United. By September 1, the only new signing was Marouane Fellaini.

Moyes recalled his efforts to sign Fàbregas, who was considering leaving Barcelona, and his failed attempt to bring Gareth Bale to United. Despite making a significant offer and arranging a helicopter for Bale, the player chose to join Real Madrid.