This faux pas heads the list of pivotal flaws racked up along his journey to the Old Trafford exit, as reported by Ian Ladyman of the Daily Mail, who details a fascinating array of errors from the former Everton boss.
Ladyman suggests that, after a conglomeration of mistakes, "the first-team squad will not miss their departed manager."
Here's a run through Moyes' reported flaws, per Ladyman's original report:
Moyes' sacking barely came as a surprise once the decision ambled out of United's headquarters. Although speculation was rife across Twitter on Monday, the announcement on Tuesday morning ended an era that—on the above evidence—was doomed from the outset.
Other reports of unrest continued to arrive during Moyes' reign. Perhaps most crucially, Moyes allegedly endured a "bust-up" with United legend Ryan Giggs, reported by David McDonnell of the Mirror. Although an alternate McDonnell article suggested the Welsh winger was "angered" with these claims, it was a prime example of Moyes' inharmonious tenure spiralling into the public sphere.
Moyes also "strongly denied" rumours of a fallout with Robin van Persie shortly into the new season, reported by Chris Wheeler of the Daily Mail. RvP later criticised the positioning of his team-mates and told Dutch television station NOS the side's play was "too slow," per Richard Hookham of the Metro.
Problems on the pitch certainly defined Moyes' era. While United's midfield had a tendency to labour under Sir Alex Ferguson, the team lost any sense of passing control under the 50-year-old.
Was David Moyes given enough time as Manchester United manager?
Possession was consistently filtered out wide and into obvious crossing positions, resulting in United breaking the all-time Premier League record of 81 crosses during a single match, per David Lynch of the Manchester Evening News.
Moyes' overcautious approach from corners often forced United players into their own box, limiting the chance of a thrilling counter. He would regularly panic when the team needed a goal, bringing Antonio Valencia on at right-back in a bid to provide United with a more attacking output, only to unbalance the side in doing so.
He also massively overpaid when landing Marouane Fellaini for £27 million and was unable to negotiate Juan Mata's deal down from a hefty £37.1 million. He missed out on key targets during the summer—including Cesc Fabregas, Thiago Alcantara and Daniele De Rossi, per Richard Jolly and Ben Gladwell of ESPN FC—as he dithered when making squad improvements.
As Ladyman's report suggests, it was a mixture of such factors that ensured Moyes would be sacked as an "astonishingly naive" blip in United's history. Staying with the manager was too risky after one season of turmoil, which was also met with the failure to qualify for next season's Champions League, forcing the United board into a major decision.
It seems the Scottish manager was never suited to tackling such a world-renowned job, or at least, he gave himself little chance to excel. Moyes' unambitious approach was reflected in his team, and if the intricacies of Ladyman's report prove to be the whole truth, it's easy to see why he lost the dressing room so quickly.
United fans and players need to move on with haste. The task of returning to Europe is going to be extremely difficult, particularly with teams such as Liverpool improving rapidly, meaning there's no time for further hiccups now Moyes has departed.