Too little, too late looks to be the thinking of the board who announced on Monday they had dispensed with the services of their Dutch manager two years into his three-year contract.
After a day of negotiations, both sides emerged on Monday night to issue the usual statements of mutual appreciation.
United thanked Van Gaal for excellent work, professionalism, dignity and his legacy of giving several youngsters a chance.
He in turn said it had been an honour to fulfil a long-held ambition to manage such a “magnificent club” although he was disappointed not to be able to see out his “three year plan.”
If Van Gaal had combined that record 12th FA Cup success with snatching a Champions League place he might have got the chance to do so but, with Jose Mourinho waiting in the wings, few will lament his departure after one of the most dispiriting seasons United fans have had to endure for decades.
For generations of United supporters brought up to expect high octane attacking football against teams who went to Old Trafford merely to survive, Van Gaal's stultifying approach was hard to swallow - particularly when it did not work very well.
This season's dire statistics, beyond the key one of fifth place, are a damning indictment of the Dutchman's tactics.
United scored 49 goals in 38 games, in contrast to their previous Premier League average of over 76 and fourth-placed Manchester City's 71.
They finished with the most 1-0 wins and the joint highest number of goalless draws in the division. Opta noted that their total number of shots on target, 430, was 15th in the 20-team league and they made more backward passes than any other side.
It was not just the supporters who were disgruntled either.
A story in Monday's Guardian newspaper said squad members had talked among themselves about openly defying the Dutchman's rigid tactical directions, which allegedly included instructions to players not to take first-time shots.
It also reported that the two most senior players, Wayne Rooney and Michael Carrick, had raised concerns with Van Gaal about his post-match “evaluation sessions” in which he publicly criticised players in front of their team mates
With such widespread dissatisfaction it easy to forget that the 64-year-old former Ajax Amsterdam, Barcelona, Bayern Munich and Netherlands coach was seen as the safe option when he was hired by United in May 2014 following Moyes's sacking.
He got the club back in the Champions League with a fourth-place finish but, despite heavy spending on the likes of Memphis Depay, Anthony Martial and Bastian Schweinsteiger, United stagnated after topping the table at the end of September.
French striker Martial apart, the new players struggled to justify their fees, and Van Gaal increasingly turned to talented youngsters such as Marcus Rashford, who has rapidly emerged from United's youth team to a place in the England squad.
By mid-December United were out of the top four after humiliating defeats by promoted clubs Bournemouth and Norwich City and they exited the Champions League after finishing third in a modest group behind VfL Wolfsburg and PSV Eindhoven.
Van Gaal became increasingly tetchy and walked out of a news conference ahead of a Christmas defeat by Stoke City.
At home to Southampton United were booed off and in Denmark the supporters, already frustrated by finding their team in the Europa League, chanted obscenities about how bad Van Gaal's side were in a 2-1 loss to FC Midjytlland.
Despite recovering with a 5-1 win in the second leg, United then lost to Liverpool in the round of 16.
A late challenge for fourth place, the Cup run and the fan-pleasing use of several young players, bought Van Gaal some time but in the bigger picture it was not enough to change the mood.
“The players are bored, fans are bored, everyone's bored,” former United great Paul Scholes said after one particularly meek Cup display against third-tier Sheffield United in January.
“You look across at the bench and Van Gaal looks bored as well,” added the former England midfielder.
Original source: FA Cup was never enough to save Van Gaal