What It’s Really Like to Risk It All in Silicon Valley

Before Nathalie Miller decided to walk away from Instacart, the grocery delivery start-up now worth more than $2 billion, she made a spreadsheet to analyze how much money she was leaving on the table.

She had been Instacart’s 20th employee, managing operations during a period of extremely rapid growth, and the sum could have been huge. She quit anyway. Like many strivers in Silicon Valley, she had a bigger plan: to start her own company that could not only make millions, but also fulfill a mission she believed in.

Her idea was to build a recruiting and hiring website that would make corporate America friendlier to women. She called the site Doxa and persuaded an engineer friend to start it with her. They strategized in borrowed office space and recruited people from other tech companies to work on the project at night, promising full-time salaries as soon as they raised venture capital.

Then, six months later, Ms. Miller discovered that she was pregnant with her first child. A baby wasn’t something she and her husband, Isaak Le, had been planning quite yet, but they were excited. Still, a sliver of doubt began to undercut her confidence about starting her own company. “How high can I stack the cards against myself — a pregnant brown woman?” said Ms. Miller, who is of Vietnamese and European descent.

Silicon Valley can seem like the land of overnight success. College dropouts show up and become billionaires a few years later. Mark Zuckerberg was a billionaire by the time he was 23, and Facebook paid $19 billion for WhatsApp when it was just five years old.

But despite their hold on the imagination, these examples aren’t typical. Much more representative are the companies you never hear about because they never get off the ground.