The average tenure of a football manager is 20 months.
The successful ones last longer, normally because successful owners at successful clubs give them longer.
Apart from clubs with a hiring and firing approach and a constant transfer spend – the blueprint for progress is invariably continuity.
So, as the dissenting voices become more audible in the wake of that horrible, horrible performance at AFC Wimbledon, the noises from Fratton Park are reassuring.
Chief executive Mark Catlin emerged from hours of talks with Guy Whittingham and his personnel on Monday night, to insist his job was not under threat.
The irritation at two weak performances on the bounce is obvious and justifiable.
But this isn’t the time for kneejerk reactions. It’s a time for cool heads.
Yes, we all would have expected better than 16th place a third of the way through the season.
It’s 16th place, however, with the caveat the team stand six points from the play-offs – with a game in hand over most rivals.
Yes the last two outings and the loss at York at the end of September were simply unacceptable.
But in between those games, was a run of six matches unbeaten, with performances, generally, of a reasonable level.
And, yes, there have been players who have not hit the highs of their pre-season billings with Pompey bookies’ favourites for the title going into the campaign.
The simple fact, however, is this Pompey side consists of 16 new faces, and the considered views among the Fratton faithful spoke of giving the team time to form.
That’s not so easy, however, when the team spectacularly fails to deliver, especially in consecutive games.
Those who saw chairman Iain McInnes storm from his seat in the directors’ box after the fourth goal at Kingsmeadow on Saturday knew what he was feeling.
That is now being explained away as an early dash for the toilet. If it was, it was an extremely angry one.
No doubt his frustration continued for the rest of the weekend.
Discussions followed on Monday with Whittingham and his team, with talk, at one stage, of a meeting between some board members and the playing staff.
That would have been ill-advised, however. Sure, most fans would have liked to have made their feelings known to the team after Saturday.
Doing so, however, would undermine the management. Those who have witnessed it before have never seen it have a positive effect.
The calls for a new man to replace Whittingham show how detached some are from the reality of where Pompey stand today.
Avram Grant, Steve Cotterill and Neil Warnock are three people mentioned recently.
That’s the same Grant who left because the budget could only stretch to paying £19,000-a-week for players, Cotterill was derided by some fans as a long-ball merchant, while Warnock commanded £15,000-a-week at Crystal Palace.
Now, 111 days into the season, is not a time for panic at the first sight of trouble.
The campaign is entering a critical period, with six of the next eight games, reassuringly, at home.
By the time January 1 arrives a clearer assessment can be made of whether the top-seven target, which most fans were aiming for in August, is on.
When Whittingham was appointed back in April, he was billed as the ‘outstanding’ candidate for the job.
If that was the view then, it’s time to back that judgement.