Christine May helped spearhead behavioral science at Noom, shaping it into an engine for user segmentation and accountability. As their former Head of Behavioral Science, she championed Noom’s “big picture” motivation model—tying everyday habits to goals—and played a role in scaling one-on-one coaching into a digital system for millions. Now, Christine helps consumer tech startups build habit-forming experiences rooted in evidence-based psychology.

In our conversation, we explore:

• The book club principle: How to embed accountability in features customers actually want

• Why 90% of users reject direct accountability features (and how to solve this)

• How Noom's lengthy sign-up flow acts as a commitment filter

• The counterintuitive confidence level that predicts user success

• What makes fixed-length plans more effective than endless subscriptions

• How to design rewards around behaviors instead of outcomes

• The unexpected way social desirability drives product engagement

This episode is packed with practical insights on designing for sustainable behavior change, creating effective accountability systems that users actually want, and the surprising psychology behind what motivates people to stick with challenging goals.

Enjoy this episode? Rate it and leave a review. It really helps others find the podcast.Learn more about Kristen and Irrational Labs ⁠here⁠.