How Being Dyslexic and 'Lousy in School' Made Shark Tank Star Barbara Corcoran a Better Entrepreneur The millionaire real-estate mogul doesn't let dyslexia hold her back. She uses it to fuel her famously feisty entrepreneurial fire.

Barbara Corcoran turned a $1,000 loan from a boyfriend into a $5 billion dollar real-estate empire. She's a celebrity investor on ABC's hit show Shark Tank, and she regularly dishes about the market's hottest luxury real estate properties on NBC's Today Show.

Still, with so many impressive accomplishments under her belt and millions of fans the world over, the fiery, no-holds-barred millionaire and former straight-D student still sweats the small stuff: She worries that people think she's stupid.

The brassy 65-year-old Edgewater, N.J., native chalks her nagging insecurity up to her ongoing struggle with dyslexia, she told Entrepreneur.com on the Shark Tank set last week. She only realized she had dyslexia all along when her son Tom was diagnosed with the learning difference in the second grade. He's now in his third year at Columbia University.

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"I feel like my whole life I've been insecure about looking not smart," Corcoran confessed. "So I feel like everything I do is a constant attempt to prove to whoever's around me that I can measure up. I'm also proving to myself that I'm always running around with insecurity."

But Corcoran doesn't feel sorry for herself and she never uses dyslexia as a crutch, she says. Instead, the former pigtailed diner waitress, who had 20 jobs before the age of 23, leverages lessons learned from coping with dyslexia to fuel her famously feisty entrepreneurial fire.

"It made me more creative, more social and more competitive," Corcoran said. "There's a great freedom to being dyslexic… if you can avoid labeling yourself as a loser in a school system that measures people by As and Bs. And the kids that are so good at school, that don't have to fight for it, very often they don't do as well in life and business because they're not flexible. There's no system dictated to them out there like it is in school and they certainly tend not to make good entrepreneurs."

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She also said some of the top entrepreneurs that brave the Tank were academically challenged and overcame their learning limitations. "A lot of them were lousy in school, too." Many didn't fit the good student mold or fit in socially. And, like Corcoran, a St. Thomas Aquinas College graduate, they're forever out to prove they're smart.

Showing the world they have the guts, hustle and, yes, wit to succeed -- "that they're not dummies after all" -- is often what motivates "a hell of a lot of entrepreneurs" to go into business in the first place.

Corcoran isn't the only dyslexic Shark to kill it in business. Kevin O'Leary, a.k.a. "Mr. Wonderful," was diagnosed with the language processing disorder when he was six. As a young schoolboy in Montreal, the Canadian financial guru was good with numbers but couldn't read.

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"It's no exaggeration to say that enrolling in special education changed my life completely," O'Leary writes in his book Cold Hard Truth (Doubleday Canada, 2011). He was lucky enough to take part in a progressive experimental dyslexia educational program in the late 1960s, back when most North American school districts hadn't yet heard of or didn't bother to formally recognize and address the disorder.

O'Leary's therapists helped him believe in himself again in a very unusual way: by convincing him to think of himself as a "mutant with super powers."

They told him, "You have the ability to read backwards, read in a mirror, read upside down," he told his alma mater, the University of Waterloo. "Can any of your classmates do that? And that actually got me back the only thing I really needed, which was my confidence."

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Shark Daymond John is also dyslexic. His meteoric rise to success -- selling handmade wool hats on the streets of Hollis, Queens to debuting his own label in the fashion houses of Manhattan -- might not have been possible had he "let his difficulty with dyslexia define him," The Yale Center for Dyslexia and Creativity said of the FUBU clothing line founder. "Instead, he used his strengths to get ahead."

Dyslexia certainly didn't stop Corcoran, O'Leary or John from making it big. Really big. Lightyears beyond the expectations of those who doubted their abilities, including their own selves.

"And what an advantage this so-called weakness is," Corcoran said. "Dyslexia and its insecurities… It sure is challenging mentally, but it sure can keep you motivated, make you money and get you places nobody else is going to get."

You can watch all of the Sharks strut their smarts on an all-new season of Shark Tank. Season Six kicks off on Friday, Sept. 26. Catch the first episode from 8 to 10 p.m. ET/PT on your local ABC station.