I was asked by a Harvard Business Review interviewer, “What is the Number One biggest issue of the successful leaders you coach?” That’s easy, I replied. Winning too much. If it’s important, we want to win. If it’s meaningful, we want to win. If it’s trivial, we want to win. If it’s not worth it, we still want to win. Why? We like winning.

There’s a fine line between being competitive and overly competitive, between winning when it counts and when no one’s counting, and successful people cross that line with alarming frequency.

Let’s be clear: I’m not disparaging competitiveness. I’m pointing out that it’s a problem when we deploy it at the service of objectives that are simply not worth the effort.

Winning too much is the Number one challenge because it underlies nearly every other behavioral problem.

It we argue too much, it’s because we want our view to prevail over everyone else (i.e., it’s all about winning).

If we’re guilty of putting down other people, it’s our stealthy way of positioning them beneath us (again, winning).

If we ignore people, again it’s about winning—by making them fade away.

If we withhold information, it’s to give ourselves an edge over others.

If we play favorites, it’s to win over allies and give “our side” an advantage. And so on. So many things we do that annoy people stem from needlessly trying to be the alpha male or female in any situation….in other words, the winner.

If you’ve achieved any modicum of success, you’re guilty of this every day. When you’re in a meeting at work, you want your opinion to prevail. When you’re arguing with your significant other, you’ll pull out all the stops to come out on top (whatever that means). Even when you’re in the supermarket checkout line, you’re scouting the other lines to see which is moving faster.

Here’s a case study that 75% of my successful clients fail: You want to go to dinner at restaurant X. Your spouse, partner or friend wants to go to restaurant Y. You have a heated debate about the choice. You end up going to restaurant Y. The experience confirms your misgivings. Your reservation is lost, and you have to wait. The service is slow, the drinks weak and the food is bad. You have two options during this painful experience. Option A: critique the restaurant and smugly point out to your partner that you were right. Option B: Shut up and eat the food. Mentally write it off and enjoy the evening.

I have polled my clients on these two options for years. I ask: what should they do, and what would they do? The results are consistent: 75% say they would critique the restaurant. What do they all agree that they should do? Shut up and have a good time. If we do a “cost benefit analysis” we generally conclude that our relationship with our partner or friend is far more important than winning a trivial argument about where to ear. And yet…the urge to win trumps our common sense. We do the wrong thing even when we know what we should do.

And it gets worse. A few years ago, I offered my coaching services free to one of the U.S. Army’s top generals. He asked, “Who would be your ideal client?”

I told him, “I’d like to work with someone who is smart, dedicated, hard-working, driven to achieve, patriotic, competitive, arrogant, stubborn, opinionated know-it-all. Do you think you could find me one?”

He replied, “Marshall, we have a target-rich environment.”

I had the opportunity to train many generals that year. In one group training session, the generals’ wives attended too. During the dinner quiz, abut 25% of the generals said they would do the right thing—shut up and enjoy dinner. Their wives stood up and said their husbands would do no such thing. That’s how strong the urge to win is. Even with a material witness in the room who they know will dispute them (their spouse), many generals still tried to give the answer that made them appear in the most attractive light.

If the need to win is the dominant gene in our “success DNA”—the overwhelming reason we’re successful—then winning too much is a genetic mutation that can limit our success.

Excerpted with permission from What Got You Here Won’t Get You There by Marshall Goldsmith with Mark Reiter, copyright 2007.