Take Sara Blakely, for example. The woman behind Spanx created the product after cutting the feet off her pantyhose and wearing them underneath a pair of pants to control her body shape. The control top made her look slimmer, but the legs kept rolling up. So she spent her life's savings, $5,000, to create a prototype that would become Spanx.
Blakely created a huge market for shapewear, revolutionizing the industry in the process. More than a decade later, she's become the world's first self-made female billionaire with a net worth of $1 billion, according to Forbes.
Business stories like this aren't the norm, but they aren't unheard of either. As the CEO of Camping World and Good Sam, Marcus Lemonis became a multimillionaire and a trailblazer in the recreational vehicle (RV) industry.
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Born in Beirut and adopted by a family that owned two car dealerships in Florida, Lemonis, who hosts CNBC Prime's new reality series "The Profit," says he definitely did not grow up with a silver spoon in his mouth.
"I would say that my parents, they're very generous," he said. "They gave me an education. They took me on vacations. But they were very matter-of-fact that if you want something, don't come asking us for it, go get it yourself."
And so he did. Lemonis always knew he wanted to be in business because he likes cash, and after graduating from college, he began working at a car dealership. But it was a conversation with family friend Lee Iacocca that set him on his current path.
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Lemonis recalls Iacocca telling him, "Look, you can be in the car business forever; you're just going to be a number."
Then Iacocca pointed Lemonis toward the RV industry.