This Tennis Pro Gives Quitting a Really Bad NameQuitting so you come out ahead is good business. Throwing your career away because you're in a bad mood is something different.

So, did you hear about the tennis player who quit right in the middle of a professional match in front of thousands of people? It's true.

It happened just last week at the Shanghai Masters. "I wasn't so much frustrated," Nick Kyrgios said in这个CBS体育报道, "I just tapped out a little bit I guess." Kyrgios not only threw point after point but also got into a fight with a heckling fan, reportedly shouting "You want to come here and play? Sit down and shut up and watch." It's not the first time this has happened. According to the CBS report, Kyrgios also gave up and lost a game on purpose in 2015 because he was mad at the umpire.

I have a problem with this kind of behavior and so would most of the successful entrepreneurs I know. Kyrgios is a decent tennis player (you have to be to make it to the level he's reached). But let's face it -- he's a lousy quitter. The smartest people I know who have done the best in business quit all the time. They're also better at knowing when.

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They sell their companies when they get the right offer. They unload stocks when they believe the market has peaked. They discontinue product lines when they're no longer as profitable as before. They terminate employees when things aren't working out. They withdraw from bidding when they feel that they won't make as much money as they need on the job.

Quitting is good. Quitting is right. Quitting is crucial to success. For smart business people quitting isn't really quitting: it's just making a decision to change what's not working.

Some people I meet don't get this. They want to stick with that sales guy because they thought he was a good hire. They want to keep selling a product even though a competitor has a better one. They want to continue providing a service even though customers aren't demanding it. They want to hold on to a dying company because their granddaddy started it last century and he would "turn over in his grave" if he knew that it was being sold.

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These are all bad business decisions made by clients I know who were afraid of quitting. Their problem is they can't separate their emotions from managing.

I know you love your business. I realize that you have a "passion" for what you do. I get it that you're trying to change the world and that your firm has provided a livelihood to people for generations. If those are the reasons why you don't want to quit doing things then you may continue to survive…you just won't be as profitable as you could be. I'm not saying that's such a bad thing. I'm just glad I'm not a shareholder in your company.

The managers who understand this know that a company is just an asset made up of smaller assets: products, people, infrastructure, equipment, real estate. Its purpose is to generate income and grow in value. It's not there to be fun, rewarding or fulfilling -- those are just ancillary benefits. When you look at the billionaires in this world –- Bill Gates, Warren Buffet, Carl Icahn, the Goldmans, the Sachs, the Walls and the Streets –- these people have made their money from buying and selling these assets. Of course they consider the human factors that make up any organization. But they know that their purpose is to make money for themselves and, more importantly, for their investors. They put aside emotions and quit when they know they can get their biggest return.

Kyrgios' biggest mistake is not quitting the game completely. His heart's not in it. He's not having a good time. He's not reaching the upper echelons of players who achieve the kind of rewards that every professional player wants. If he's giving up a game and fighting with a fan then it's clear tennis has become a burden, not an enjoyment. His value is declining.

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For him, it's time to sell, to quit, to move on. Otherwise he's just wasting his assets –- his body, his time, his credibility –- on a profession that's not profitable for him. Sound familiar? He can do other things with his life that may be more enjoyable and profitable while still having a good time playing tennis on the side. On the professional circuit, he's an above average player. But if you ask any successful entrepreneur, they'd tell you he's a very below average quitter.