Why Leaders Don't Behave the Way They ShouldWe are creatures of evolution. That's why taking a calm, measured approach to management is always easier said than done.

Where is it written thatleadersshould act as if they were injected with enough steroids to turbocharge a racehorse? What business bible teachesmanagersto be heavy-handed, hotheaded, testosterone-fueled taskmasters?

Maybe that was conventional wisdom back in the 1950s, but in these enlightened times, we should know better, right?

Come on, get real. Maybe we should know better, but the truth is we don't. Many, if not most, of us still do it. Try as we might to be more levelheaded and balanced, more emotionally intelligent, more in touch with our yin than our yang, we still end up coming across like a drill sergeant.

Sure, if you spend all your time in the feel-good blogosphere you get the impression that the old school command-and-control style of management is dead and everybody has their Neanderthal brains safely chained up in a deep dark dungeon somewhere.

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Maybe in the utopian world, but in the real business world, that simply isn't true. There are lots of reasons for that, and some of them are actually good ones. For one thing, old habits die hard. And when push comes to shove, as it so often does in a competitive world, we humans have a real tendency to push and shove.

Actually, each andevery one of us has a limbic system– the "feeling and reacting" portion of our brain that's responsible for self-preservation. The limbic system regulates autonomic and endocrine function, including our fight-or-flight response to emotional stimuli.

And get this: the limbic system predates the far more civilized neocortex or "thinking" portion of your brain by millions of years of evolution. In other words, it's not easily overruled by logic, reason, an executive coach, or an article you read yesterday that says you'll be a better leader and far more successful if you tone it down a bit.

But there is hope. I know that because my limbic system was stimulated by an overwhelming sense of hope I felt watching last Thursday night's football game on the NFL network. Even if you're not into America's sport, bear with me. It'll be worth it. I promise.

The Indianapolis Colts were getting beaten by the Tennessee Titans 17-6 at the half. Actually, the Colts were more or less beating themselves, courtesy of a long string of needless misconduct penalties that cost them at least one touchdown. Clearly, the Colts defense was being too aggressive, especially considering the NFL's new nanny rules designed to protect "defenseless" players.

所以你希望球队的主教练,查克·Pagano, to tear the players a new one in the locker room at halftime. But that's not what happened. Instead of going nuclear on his players, the coach simply told them to "keep up the physicality, but keep their composure," according to NFL network reporter Alex Flanagan.

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The Colts played like a different team in the second half and ended up winning the game, 30-27. Had coach Pagano gone overboard instead of taking a more nuanced approach, the result might very well have been different.

Now, some say Pagano's coaching style lightened up quite a bit after he survived Leukemia last year. Indeed, I've seen that phenomenon before. Someone close to Andy Grove once told me that the famously caustic and confrontational former chief executive of Intel changed dramatically after a bout with prostate cancer. And I once had a CEO who was similarly affected by a near-death experience.

The reason we're more susceptible to change during times of personal crisis is because real behavioral change requires participation by the limbic system. In other words, your neocortex can think "I should change," but unless there's a real or perceived threat to your survival, your limbic system just sort of shrugs its shoulders and goes about its business as usual.

That's why personal crises are often called life-altering events. They affect you emotionally, and that's often what it takes to get through that thick skull of yours.

So now you know why, just like you, leaders don't always behave the way they should. Individuals have many facets and the human brain has lots of moving parts. You may want to change, think you should change, or even know you should change, but that doesn't necessarily result in a change of your behavior.

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