So now we know. Chopping and changing managers is bad for a football club's health. The biggest academic study of the subject ever undertaken, published yesterday, shows that the English league clubs who have changed their managers the most times have significant worse results than those who have had the fewest managers.
There were 678 managerial changes in England's top four divisions between August 1992 - when the Premiership started - and 4 January this year. When resignations and departures by "mutual consent" were deducted, the study found there have been 536 sackings since 1992, or an average of 41 per year.
This has created an atmosphere of "damaging instability" for the football industry as a whole, and especially for individual clubs who have made the most changes, according to Dr Sue Bridgewater of the University of Warwick.
And the "life expectancies" of managers do not look like improving. In 1992/93, a manager could expect to stay in his job for an average of 2.72 years. The comparable figure now is 1.72 years.
Clubs with 10 or more permanent managers in the study period, including Crystal Palace (13 managers), Southampton (12), Notts County, Barnsley, Stoke and Cardiff (all 11), have won an average of 32.53 per cent of games. The nine clubs who have had three or fewer managers since 1992, including Charlton, Crewe, Manchester United (one each), Wrexham (two) and Arsenal, Ipswich, Liverpool, Middlesbrough and Port Vale (three), have won an average of 43.03 per cent of matches.
Case studies of clubs at the extremes of the managerial hiring-and-firing scale indicate that stability brings success. Manchester United stood by Alex Ferguson through some indifferent early seasons to be rewarded with eight League titles and a range of domestic and international silverware. Crewe, under Dario Gradi's guidance for more than 20 years, have been transformed from Fourth Division nobodies to punch above their weight in the Championship. Charlton under Alan Curbishley have moved from the old First Division to establish themselves in the Premiership.
Conversely, the frequent changes of manager at Southampton, especially in the last two years, ended in relegation from the top division after an unbroken stay of 27 years. While several of the managerial departures from the club in the past decade came via resignations, not sackings - Alan Ball, Graeme Souness, Glenn Hoddle and Gordon Strachan all left of their own volition - other hasty changes, particularly the removals of Paul Sturrock and Steve Wigley, were part of a decline that led to the drop.
But does Dr Bridgewater's research prove that clubs who chop and change end up with worse results? Or have bad results necessitated a frequent change of managers at some clubs? Dr Bridgewater says her work shows clear statistical evidence that frequent change leads to bad results, not vice versa.
Dr Bridgewater has identified factors that contribute to a club's ability to win matches. Some are beyond the manager's immediate control, such as the size of a club, its financial strength and the amount of transfer funds available to him. Other factors are a manager's length of experience in the game, the years in any given post, and the professional qualifications a manager has. Greater experience correlates, statistically, with greater success, as does the length of time in one job.
The report also shows "a significant change in fortunes of managers brought about by the increasing uptake of relevant professional qualifications". The research team found that managers with no qualifications, or only the more limited "B" licence, achieved, on average, a 30 per cent win rate, while those with the Pro Licence averaged a rate of 37.09 per cent.
John Barnwell, the chief executive of the League Managers' Association, said yesterday that he was grateful that Dr Bridgewater's research had verified that time in the job generally equates to better results.
"I've kept on saying it because I believe it," he said. "But it's reassuring that such a detailed academic study now also proves it. I hope football in the widest sense takes note, and that we can all learn from this. Stability is the key to success in any industry and football is no different."
Barnwell added that two managers who have benefited from gaining all the relevant professional and managerial qualifications on offer are Manchester City's Stuart Pearce and Watford's Adrian Boothroyd.
Pearce, who has completed his Pro Licence and gained a Certificate in Football Management, said: "The bottom line is the more education you can give yourself, and the more preparation you can do, the less chance of failing."
Dr Bridgewater's analysis shows that lower-league managers are more likely to be sacked than those in the top flight. This is possibly because top-flight managers mostly arrive there having gained experience, itself a factor in holding on to a job.
The trend in sackings has been gradually upwards since 31 managers - across all divisions - were dismissed in 1992/93, although the peak was 2001/02, when 56 were fired, 10 of them in the Premiership. The collapse of ITV digital and the financial crisis below the Premiership were said to be factors in 46 non-Premiership managers losing their jobs.
"There is no clear relationship between the general rise in dismissals and the performance level of managers," Dr Bridgewater said. "Sacked managers these days are doing no worse in results terms than sacked managers back in 1992-93, but more are still losing their jobs."Reuse content