Louis van Gaal has made plenty of mistakes during his time at Manchester United. He has been afflicted by some unfortunate luck with injuries, certainly, and the club hierarchy's inexperience in the transfer market appears to have hampered the squad building he has attempted.
However, there are also plenty of things for which he has to take responsibility.
Here are a few of his most key errors.
The Angel Di Maria Affair
Of all the players that United have signed during the Van Gaal era, Angel Di Maria really should have been the one.
During his debut at Burnley, the Argentina international looked—by some distance—the best player on the pitch.
When he made his home debut, against Queens Park Rangers, United looked unrecognisable from the dross that had been served up under David Moyes. Di Maria was electric, blasting down the left wing and causing havoc every time he did so.
How United had missed a creative and purposeful No. 7. The player who had been man of the match in the previous season's Champions League final, who had been absolutely integral to Real Madrid's success and who had helped fire Argentina to a World Cup final was truly at Manchester United.
Madrid's bizarre decision to let the player be sold was United's gain.
But it did not last. It is not entirely Van Gaal's fault, of course. On 5 February, Di Maria told L'Equipe (h/t Manchester Evening News), "Manchester was a sad experience. Things did not go the way I expected, I was disappointed and I could not surface."
His sadness was evident on the pitch, there was an almost palpable lack of effort on occasion. But Van Gaal's rigid footballing discipline was a terrible match for the creative and improvisational Di Maria.
He failed to get the best out of the Argentina international, never quite building the team around him in the way he should have done, never finding a way to address the personal issues Di Maria was facing.
United lost out on a player with the potential to have helped transform their fortunes, and Van Gaal has to take a hefty share of the responsibility for that failure.
Overreacting to Leicester City
Of all the alternative histories of Van Gaal's time at United that could be written, the one which would be most fascinating would be the "What If?" story that examined a future where United had held on to their 3-1 lead against Leicester City in September 2014.
To paraphrase a risque quote from Van Gaal, per Jamie Jackson of the Guardian, United's lack of defensive stability made the manager "twitch."
Van Gaal's refusal to do what Sir Alex Ferguson had done previously and just gamble was a problem for fans, and it did not result in a particularly impressive finish in the league by the end of the season.
From the free-flowing attack that United had shown in the first half at the King Power Stadium came static and overly defensive performances which have lasted into this season. Van Gaal should have written that game off and carried on trying to entertain.
Spending too Long Trying to Accommodate Stars
It would be a challenge for any manager in the world to accommodate Di Maria, Radamel Falcao, Robin van Persie, Wayne Rooney and Juan Mata in the same starting XI in anything like the positions in which they can be most effective.
Van Gaal played both Mata and Rooney in central midfield and played Di Maria in almost every attacking position on the pitch.
Instead of choosing the players he believed in and stuck with them, he tried to squeeze all his stars into the same side—it rarely worked.
It was not until he was denied the services of Di Maria through suspension, Van Persie through injury that and Falcao through a collapse of form that he hit upon a truly effective blend. He should have been bolder in leaving his underperforming stars out of the side.
Overinvestment in Wayne Rooney
And speaking of leaving underperforming stars out of the side...
Rooney has been rendered undroppable under Van Gaal. This season he has been rested for one half of football in the league, and otherwise has only been left out due to injury.
In Van Gaal's defence, Rooney did eventually play himself back into form. It was just that it didn't happen until January, by which time United's season was effectively over.
The England international should have been dropped or at least rested and rotated a little in those long stretches of poor form.
Instead, Van Gaal stuck with him through thick and—mostly—thin, costing his side dearly when a more mobile and potent goal threat up front would have helped tremendously.
Blaming Paul Scholes
Unbelievably, Van Gaal returned to the theme of blaming Paul Scholes for the negative perception of his football in an interview with Mark Ogden of the Independent on 12 February.
Months after the initial spat had blown over, he suggested again that Scholes had brought about a change in atmosphere around Old Trafford, saying:
...when Paul Scholes started [criticising the style of play] he influenced a certain amount of fans.
What Scholes is thinking, he has to think it. Every human being can give his opinion. I don’t bother about that, I think it is good. But my problem is when you create an atmosphere, a very negative atmosphere for somebody, so maybe he should be more positive.
Van Gaal's comments are an affront to most United fans. As well as holding Scholes in considerably higher esteem than the Dutchman, they also have every right to find their intelligence insulted.
Van Gaal has mistaken effect for cause, here. Scholes' criticisms were a reflection of what many fans felt. They did not shape the atmosphere among fans so much as give it a public voice.
The manager was essentially denying responsibility for the dissatisfaction with the drab football on show by passing the buck to Scholes.
It is transparent, insulting and simply wrong.
Abandoning 4-3-3 / Insistence on Two Holding Midfielders
Before this season began, Van Gaal was asked whether he planned to play 4-3-3 during the season ahead, and replied, per Manchester Evening News:
More or less 4-3-3. We played that already last season, in the second half of the season, and I have said that is the system I want to use.
We played in our shape and played how we have to play. That's also where I have been very satisfied.
However, most tactical analysts would call United's typical formation this season 4-2-3-1, with two holding midfielders distinct from the more advanced central attacking midfielder.
When United were at their best under Van Gaal, they played just one holding midfielder.
He has rarely returned to that, in spite of saying he would. This season the formation has been much more static and inherently less attacking. No surprise, then, that the Red Devils have been involved in seven 0-0 draws to date.
Wasting Mata on the Wing and Herrera on the Bench
Juan Mata was excellent as a false right-winger in last season's 4-3-3, but this season he has been wasted on the right of a 4-2-3-1, where he is expected to do more defensive work, and wherein there are fewer players breaking from midfield to create space.
United have generally been better since he moved to No. 10, and his performances have also improved. He moved inside against Derby County on 29 January and scored his first goal since 7 November. He hit the target again at Shrewsbury Town on Monday.
And as for Ander Herrera, his form may have dipped this season, but surely that is understandable given Van Gaal's baffling reticence to include him more regularly in the starting XI.
Last season he was easily one of United's most important outfield players. By the second half of the campaign, he seemed firmly established in Van Gaal's plans.
However, this season began with Herrera once again rotated in and out of the side. Gone was the fluency and attacking purpose from midfield.
It will be intriguing to see how any new manager handles these two players.
Van Gaal has got some things right too, and he will leave United stronger than he found it in terms of squad balance, with plenty of bright young things emerging.
However, he has made too many mistakes to succeed, and as a consequence he will not be missed much when he does either call it a day or is removed from his post to allow another manager to take the reins.