Trusting Your Gut When Building Your Business Advice from Shark Tank's Barbara Corcoran.

I've listened to my gut on every good business decision I've ever made. I've learned the hard way that ignoring my instinct is always an expensive mistake. I've lost my money on many Shark Tank deals because I didn't listen, but fortunately I listen most of the time!

When young Tiffany Krumins stepped onto the Shark Tank set, this nanny-turned-BIZ Experiences took one deep breath and looked each of the sharks straight in the eye. From the way she was dressed I figured she was a virgin, but Tiffany dove straight into her pitch and I thought, this girl is hot stuff and she's not the least bit intimidated! With her wide-eyed innocence, I felt she couldn't see a freight car coming until it had hit her.

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Tiffany's invention was a small blue elephant head with a medicine dropper tucked neatly in its trunk. She named her product "Ava the Elephant" and as she pressed the little sound button on the back, the sweet voice that we heard was none other than that of the inventor herself. "One, two, three … open wide…Good job!" She claimed that children who used her dispenser happily took their medicine. Tiffany ended her presentation holding up her clay model and said, "I promise you that Ava works every single time! I don't care what medicine your kids hate, they'll open up their mouths and take it from Ava with a smile!" Totally convincing.

The male sharks smiling at Tiffany obviously thought she and her little elephant were cute, but I could see right away they were not taking her seriously. They behaved like men do when doing a favor for the daughter of a friend, but they were sure as heck not going to put their money on the table. My impression of young Tiffany was different and I had learned to trust my gut. Tiffany might look innocent, but I instinctively sensed a backbone made of steel. So I moved in for the kill, buying 51 percent of the Ava the Elephant business before the other sharks could rethink their positions.

Related: Barbara Corcoaran: Failure Is My Specialty

Kevin O'Leary scoffed at the "Outrageous price of $50,000 for such a silly business!" after Tiffany left the set. But the next morning, his young wife reprimanded him, "You shouldn't have passed on that clever medicine dispenser, Kevin" she chided, "Men don't have to get up in the middle of the night to get their kids to take their medicine. You might not get it, but women will." The women viewers at home did get it and today the dispenser is sold in most large pharmacies in America. What's more, thanks to me trusting my gut, Ava has made me a tidy $280,000 profit!