Superhuman Mail users respond to 72% more emails per hour and save an average of four hours every week — numbers backed by a case study from one of the Big Three strategy consulting firms. Rahul Vohra, CEO at Superhuman Mail, built the world's fastest email engine over three years without launching, held the line until the product was ready, and then productized product-market fit into a repeatable, measurable science. Following Superhuman's acquisition by Grammarly in 2025, Rahul is now steering the company toward a unified AI-native productivity suite spanning email, calendar, tasks, and agents.

What you'll learn:

The 5-step PMF Engine: how to survey, segment, analyze, implement, and track your way to product-market fit with a numerical score
Why you should ignore the not disappointed and most somewhat disappointed users — and which signals actually tell you who to build for
How to use the High Expectation Customer (HXC) framework to narrow your market without changing your product
Why PMF is a moving target and how to defend it against commoditization and copy-cat competition
How Rahul operates as the editor of the product — using 20 verbatim quotes to push PMs and designers to sharper decisions

Key takeaways:

If more than 40% of your users would be very disappointed without your product, you have an initial PMF — and you can measure your way there
Changing your market is faster than changing your product — segmentation alone can jump your PMF score 10 points overnight
Building for your highest-expectation customer is not the same as building for your ICP — confuse the two, and you'll optimize for the wrong signal

Credits:
Host: Carlos Gonzalez de Villaumbrosia
Guest: Rahul Vohra

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