The surprising dinner table question that got billionaire Sara Blakely to where she is today

Most kids are asked questions like, "What was the best part of your day?" or, "What did you learn at school today?" at the family dinner table.

Sara Blakely, founder of the billion dollar hosiery and apparel company Spanx, had a bit of a different dinner time experience growing up.

"My dad used to ask my brother and me at the dinner table what we had failed at that week," she told the audience at a recent Network for Teaching Entrepreneurship event in New York City. "I can remember coming home from school and saying, 'Dad, I tried out for this and I was horrible!' and he would high-five me and say, 'Way to go!' If I didn't have something that I had failed at, he actually would be disappointed."

This dinner table tradition allowed Blakely to see the value in failure. "My dad always encouraged me to fail, and because of this, he gave me the gift of retraining my thinking about failure," she explained. "Failure for me became about not trying, instead of the outcome."

Having never taken a business class and having zero background in the fashion retail industry, Blakely's investment in Spanx was a risk to say the least, but one she didn't mind taking.

Her gamble paid off - in addition to becoming the world's youngest self-made female billionaire at age 41, Blakely also made Time Magazine's prestigious 100 Most Influential People list in 2012.

"A lot of entrepreneurs are held back from the fear of failure, so that lesson from my dad was a real gift," she told the audience.

Rather than letting fear of the unknown or of not being good enough dictate your decisions, Blakely encourages aspiring entrepreneurs to use inexperience and weaknesses to their advantage: "What you don't know can become your greatest asset if you let it."