On Wall Street, barely sleeping was a badge of honor. It inspired me to quit and launch a health startup.

Josh Hou, on the right, with his Ren cofounders Ryan Hou (left) and Eli Qian (middle). Josh Hou Josh Hou, 22, left his investment banking job at Evercore after a year to cofound Ren, a health app. Conversations on Wall Street about sleep and the culture around wearables inspired the startup. Hou…