Welcome to episode 55 of Inc.'s Founders Project with Alexa Von Tobel podcast, where we bring you stories of the entrepreneurs building the future. Listen to the tales of guts, inspiration, and drive that define the people and companies at the forefront of technology. Each week, we dig into a founder's professional playbook--and uncover what makes them tick.

How to Quantify Product Market Fit, with Rahul Vohra of Superhuman

Why is "inbox zero" so hard to reach? After building Rapportive, the first Gmail plugin to scale to millions of users, Rahul Vohra was ready to tackle the problem of email itself. In 2014, he started Superhuman with the goal of building the fastest email experience in the world. If Superhuman's waitlist of over 300,000 people is any indication, he's done just that. Vohra explains why domain expertise matters, how he learned to choose a strategy and stick with it, and why you have to figure out positioning before pricing.