Despite all the forensic swabbing of each cough and spit from David Moyes's short reign at Manchester United – from tactics to transfer red herrings via potential rifts and tiffs – the key question has not been asked.
Exactly what would constitute success next May?
It is a question that every league club should put to themselves each August, otherwise they are just hiring and firing while groping in the dark. You suspect they do not.
After all, during the 2012-13 season, 43 out of 92 managers in the four English divisions were sacked. Which suggests either a staggering level of incompetence or completely unrealistic expectations. I know which my money is on.
We already know the crude answer to how Moyes will be judged at the end of the season. If he wins a major trophy – and no, the Community Shield does not count – he will probably be deemed a success. If he does not, he will fear the managerial equivalent of the bends.
A starting point to find a better "par" score for Moyes comes via the bookies, who have eased United's odds of succeeding this season since his appointment. Just before Sir Alex Ferguson resigned, they were 13-8 for the 2013-14 Premier League title, odds that imply a 42% chance of victory. Now they are 5-2, a 28% chance.
However, the bookies still expect Moyes to win at least one major trophy in 2014. He is 8-11 – an implied chance of 58% – to do so and 5-4 to not do so, a 44% chance.
That is one measure to gauge Moyes's success. Another is to use statistical models that predict a team's points tally – such as the Euro Club Index created by Infostrada and Hypercube – by ranking all Europe's top-flight clubs using results in all competitions from the last four years, weighted for recency.
Before the 2012-13 season, the Euro Club Index forecast the top seven Premier League clubs in the correct order and it has made an 8% profit with match predictions over the past three seasons.
In 2013-14 it suggests that United will amass 82 points and that they have a 38% chance of winning the league – although its model does not account for player or managerial changes.
But there is another question we need to consider in Moyes's case: how do those who succeed highly successful managers perform? We can all spit out examples of failure or success but John Goddard, a professor of financial economics at Bangor University, has been far more systematic. He has examined every managerial spell – all 1,889 of them – across all four divisions of English football from the late 1960s to 2012-13 and his research suggests that a slight downturn in United's fortunes would not be a great surprise.
Goddard looked at two measures of a manager's success – length of time in the job and win ratio (calculated by awarding one point for a win, 0.5 points for a draw and zero for a loss, and dividing the figure by league matches) – and then looking at how each replacement performed.
Using both measures he found that there was, on average, a drop-off in performance.
First he examined success based on the length of time in the job. This included looking at the reigns of managers such as Ferguson at United, Dario Gradi at Crewe and Brian Clough at Nottingham Forest, and seeing how their successors fared.
Those who replaced the top 10% of longest-serving managers were given an average of 119 matches before losing their jobs – significantly higher than the average of 97 games – even though their win ratio was 0.486, below the average of 0.5.
As Goddard points out: "This suggests that after having employed a successful manager for a long period, chairmen were inclined to stand by the replacement for longer than they otherwise would, even though they tended to underperform."
Goddard then looked at the top 10% of managers by win ratio – and how their successors performed.
Once again, the win ratio (0.463) dropped to below the average of 0.5 for all managers in his database.
However, the picture changes slightly when you focus on the creme de la creme of English football managers and their successors over the last 40-plus years.
Excluding spells of fewer than 50 matches, the top-ranked manager in terms of win ratio was José Mourinho at Chelsea between 2004 and 2007, with a score of 0.813. He was followed by Kenny Dalglish at Liverpool from 1985‑91, on 0.732, and then Sir Alex Ferguson at Manchester United (1986‑2013) on 0.718.
Of the top 10, only two successors have done better in terms of win ratio – Bob Paisley following Bill Shankly and Dalglish after Joe Fagan.
Meanwhile, the average win ratio or the successors to the 10 best-performing top-flight managers is 0.657 – quite a bit down on Ferguson's 0.718. That would equate to 73 league points.
You doubt that United fans would be happy with that. But it may yet be that a trophy and a Premier League tally of between 73 and 82 points, lower than the 89 of last season, would not be an unrealistic return for Moyes's first year at Old Trafford.
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