Working in tech, Nancy Marzouk was used to being the only woman in the room. But that doesn't mean she liked it.

"I felt like I constantly overperformed, yet was under potentially more scrutiny than other people, if that makes sense," said Marzouk, 52.

She'd gone to school for fine arts, but fell into advertising after undergrad and grew to love the industry. As she rose in the ranks at various marketing and tech agencies, she felt like she was always working harder than the people around her but wasn't moving up the ladder at the same rate.

"The companies weren't going to change. I had to leave to change it, basically. That's how I felt," she said. "I felt like I had gotten to the point in my career where it wasn't about what I did. There was too much politics at play. And so, if you weren't part of that, like, boys' club, then ... it didn't matter what I did."

Marzouk took a risk. She left her stable corporate job and launched her own startup, MediaWallah, a data management company, in 2013. Now, Marzouk makes between $600,000 and $800,000 every year, placing her in the top 1% of income earners in the country, according to SmartAsset.