Joe Girardi’s 10 Yankee teams had a cumulative record of 910-710, the best of any team in Major League Baseball over that span. That means that the year the 2017 Yankees had, in which they went 91-71, was their average year with Girardi as their manager.

In 10 seasons, Girardi’s Yankees made six playoff appearances, won 28 playoff games and a World Series, a record most franchises would kill to have.

And this October, Girardi’s Yankees won four elimination games and came within one win of going to the World Series, with a roster that was supposed to be in transition.

So if you are looking for reasons why the Yankees chose to part ways with Girardi on Thursday, you will not find it in the numbers.

Not even general manager Brian Cashman, as nerdy as the cast of The Big Bang Theory when it comes to analytics, could come up with a metric to justify letting Girardi walk now.

No, to understand why Joe Girardi is no longer the manager of the Yankees, you have to dig a little deeper, while at the same time making things a little simpler: Clearly, the Yankees did not think the tightly-wound Girardi was the right manager to lead a roster full of young, impressionable – and still malleable – kids.

Girardi’s attributes as a manager are many. He is meticulously prepared, has a work ethic that leave a Marine drill sergeant gasping for breath, and refuses to concede as much as a single pitch even in a spring training game.

But the flip side of that is a man who often seems joyless even when winning and whose tight-lipped demeanor could easily be viewed as spreading its tension throughout his clubhouse. And it is possible – I am not saying this is anything more than my informed opinion – that the Yankees front office feared that Girardi’s grim intensity could be hurting some of his young players.

It was different, of course, when Girardi was managing a team of veterans, who pretty much ignored the manager and went about their business. Players like Derek Jeter, Alex Rodriguez, Andy Pettitte, Jorge Posada, Carlos Beltran and Mark Teixeira did not need to be “motivated’’ by a manager, nor told how crucial any particular game was. And because they had proven track records, they were not likely to succumb to Girardi’s tendency to impatience and even panic, which easily could sow doubt in the minds of less-accomplished players.

Just look at how Girardi handled the struggles of Dellin Betances late in the season. Despite the words of support he would dutifully mouth in the postgame interview about how he still believed in Betances, his actions said otherwise, and never was that clearer than in Game 5 of the ALCS against the Astros, when even with an eight-run lead Girardi couldn’t help himself from pulling him after he walked the first two batters he faced.

Yes, it was a must-win game, but obviously, Betances could not give up a nine-run homer, and if ever there was an opportunity to allow a young pitcher to work out his problems in a game situation, that was it. But by yanking him so quickly, Girardi let Betances, and the world, know he no longer trusted him. And as long as Girardi remained the manager, whenever Betances fell behind on a hitter, he would forever be looking over his shoulder expecting the manager to come out and get him.

That kind of fearful attitude could also have been in the minds of Gary Sanchez over his defensive liabilities, Sonny Gray over his command problems, and Aroldis Chapman, who lost his closer’s job in a hurry midway through the season.

All those players, as well as Aaron Judge, Aaron Hicks and Chad Green – who Girardi misused in Game 6, burning him with the Yankees trailing 6-0 and leaving himself short in the bullpen for Game 7 – are the future of the Yankees.

Obviously, the Yankees front office decided Girardi was not.

In my interactions with team and baseball sources on Thursday, several things became obvious. One, Girardi’s missteps in the post-season, most notably his failure to challenge the controversial hit-by-pitch call in Game 2 of the ALDS, had no real bearing on this decision.

Two, the call was made by Hal Steinbrenner, who has often been considered softer than his old man, on the recommendation of Cashman, generally assumed to be an ardent Girardi booster.

And three, the decision not to renew Girardi’s contract may have been made months ago, according to a baseball insider with direct knowledge of the inner workings of the Yankees front office.

That all adds up to only one possible conclusion: No matter what the 2017 Yankees wound up accomplishing, it probably wasn’t going to be enough to save the manager’s job.

Somewhere along the line, the Yankees front office came to believe that Joe Girardi was not the right man to lead the Baby Bombers into the future, even if the numbers told you otherwise.