Entrepreneurs who are just starting out should brace themselves to hear the word "no" over and over.
"When you start a company, everybody will tell you, 'No, no, no,'" said serial entrepreneur Martine Rothblatt, a founder of Sirius Satellite Radio and biotech firm United Therapeutics.
"You'll hear 99 — maybe 999 — no's before you get to a yes," she said.
Rothblatt certainly knows a thing or two about overcoming obstacles. After co-founding Sirius in 1990, she made a career 180 when she learned that her youngest daughter had developed a fatal illness called pulmonary hypertension, which lacked approved medicines to treat it.
Despite having taken her last biology and chemistry classes years earlier in high school, she doubled down on finding a cure and founded United Therapeutics in 1996.
"When you're motivated to cure your daughter, you're going to do everything," she said. "I just went to the library to become competent enough to find a molecule that would at least halt the progression of her disease."