5. An 'itch' is not enough to build a business on, and the big idea can take a while to come.
For Anastasia Leng, the entrepreneurial call came more subtly, like an itch that wouldn't go away, about three years into her tenure at Google.
"I started to feel too comfortable," she said. "I started looking at other jobs, other start-ups, but nothing felt right. One piece of advice I got from someone was that every two years, pop your head up and see what else is out there—if you don't find anything, put your head down; the worst place to be is one foot out the door."
Leng eventually switched to a different division within Google—business development, which exposed her to dozens of early-stage exploratory deals—but "about two years went by, and I found myself getting that same itch," she said.
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The lightbulb moment struck when a couple of friends were planning their weddings and couldn't find accessories exactly as they wanted them. Leng started to envision a marketplace where consumers could liaison with designers to get products in the exact shade or material they wanted.
"Once that nugget of an idea popped into my head, everything happened very quickly," Leng said. She left Google a few months later, in August 2012, had a website up by November and $1 million in seed funding by May 2013. "The biggest thing gnawing at me was that I didn't want to wake up 20 years down the road and be the person who talked about doing something but never did."