The 5 Best Business Mantras From 'Mr. Wonderful' I recently met with Kevin O'Leary, one of the judges on ABC's "Shark Tank," and came away with some memorable lessons.

We all know Mr. Wonderful. He's the shrewd and sometimes insolent shark on ABC's Shark Tank. Whether you love or hate him, there's one thing we can agree on: he speaks the unfiltered truth. I recently met with Kevin O'Leary to talk about business, entrepreneurship and life. The best part of our meeting was that I left with five of the most memorable business mantras ever.

1. If it's got rabies, kill it.

O'Leary says that he can't stand when his fellow sharks endorse terrible business ideas. He notes that the other sharks don't want to hurt the feelings of a budding entrepreneur so they will send them off the show with a pat on the back and kind words about their business idea. This type of coddling, O'Leary says, is an absolute disservice to that entrepreneur.

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Sure, the truth hurts sometimes, but O'Leary says he has no problem telling someone that their idea is bad and doomed to fail. He says that if an animal has rabies, you don't send it off to get better, you kill it. He feels it's his obligation to do that for contestants who come on the show with really awful business ideas.

2. Work for the white space.

O'Leary keeps a crazy schedule. He gives all credit to his assistant, Nancy, for keeping his life on track. She color codes his calendar based on what type of appointment it is. He says that the goal of every entrepreneur should be to control the space on your calendar.

Some of the calendar should remain white each month, O'Leary insists. This is his time to do what he wants. He says that what every entrepreneur really wants is freedom, and so the goal should be to get to a point in business where you have plenty of white space on your calendar to do what you love.

3. Killing money is a crime.

This is one of the reasons why O'Leary has no problem telling an entrepreneur when they have a lousy idea. He hates seeing good money being thrown out the window. That being said, as a shark he's always looking for entrepreneurs who have solved a problem that nobody else has solved.

For example, O'Leary says that Wicked Good Cupcakes is one of the most successful businesses he has invested in on Shark Tank. Its cupcakes are sold in glass mason jars. Not only are they the best cupcakes you will ever eat, he says, they stay fresh in the jars and are easy to ship for gifts across the country.

Related: Robert Herjavec: 'The World Doesn't Reward Mediocrity.'

4. I'm your best friend. I don't care about your feelings.

In seeking advice for any business, O'Leary says to find mentors, coaches and business advisors who don't care about your feelings. This is the strength that O'Leary says he brings to the table on Shark Tank. He notes that it's important to find people who will tell you real advice, based on the business idea at hand, not on the emotions of the entrepreneur.

5. If you want something done, hire a busy mom.

At the start of 2015, O'Leary wrote off one-third of the 27 businesses he still held in his business portfolio from Shark Tank. He then analyzed the remaining businesses to see what they had in common so that he could make better investing decisions in the future. What was the one common thread that all of his high performing businesses had? They were all lead by women.

O'Leary says that he's come to believe that if you want to find entrepreneurs who get things done, then find busy moms who are juggling a million things at once, because somehow they also manage to run and grow great businesses.

For example, Tracey Noonan and Dani Vilagie, the co-founders of Wicked Good Cupcakes. They are constantly traveling and doing media while also growing the business, improving processes, inventing new products and helping other family members who need them personally. O'Leary says he holds a deep admiration for working moms and when it comes to entrepreneurship, often sees their business ideas as a sound investment.

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