Starting a company isn’t easy, but according to three of Fortune’s most extraordinary female founders of 2015, it’s is one of the most rewarding and fun things they’ve ever done.

Gathered Table co-founder and CEO Mary Egan, Revel Systems co-founder and CEO Lisa Falzone and StyleSeat co-founder and CEO Melody McCloskey shared their startup stories and advice with a packed audience at Fortune’s Most Powerful Women Next Gen Summit 2015 in San Francisco earlier this month. The conference gathered some of Silicon Valley’s top female business leaders and innovators to discuss topics ranging from unconscious bias and the gender pay gap, to the new consumer-driven economy and women on boards.

The good, the bad and the ugly of entrepreneurship was a theme that bubbled up throughout the two-day summit.
“It’s not an easy life,” admitted Falzone, “but it’s the most rewarding thing you’ll ever do.” Her company, Revel Systems, makes iPad-based point of sale systems for retailers and restaurants.

StyleSeat’s McCloskey agreed, calling the first year of her startup “insane” but at the same time, “rewarding and so much fun.” Her startup StyleSeat is an online marketplace for beauty and wellness services.