Chinese billionaire Zhou Qunfei is the world's richest self-made woman, according to Forbes, and she attributes her success to one thing: perseverance.
Zhou, the 48-year-old CEO of Lens Technology, has built an empire manufacturing glass for tech giants such as Tesla, Apple and Samsung, but it hasn't been an easy ride to the top.
"I have encountered many difficulties and setbacks as an entrepreneur," she tells CNBC Make It. "If I gave up then, there wouldn't have been Zhou Qunfei or Lens Technology."
The hardship started early. Zhou's father, a skilled craftsman, went blind and lost a finger in a factory accident before she was born, and her mother died when she was 5. "I had to constantly think about where my next meal is and how I am going to get it," she says.
In 1986, at age 16, Zhou dropped out of high school to work as an assembly worker in a watch lens factory. She took accounting classes at night and dreamed of starting her own business.
By 1993, she'd saved 20,000 HK dollars (or about $2,500) to set up her first company — a family watch lens workshop. She and her seven cousins and siblings worked and lived together in a three-bedroom apartment for four years.