In this episode of the podcast, we explore Duolingo Streaks—a feature that might seem straightforward but has played a crucial role in the company's growth and valuation. Jackson Shuttleworth, a Group Product Manager at Duolingo, shares valuable insights from over 600 A/B tests on this feature. He discusses how Streaks evolved from an XP-based system to a lesson-based model, emphasizes the need for user clarity and understanding, and explains the strategic role of flexibility mechanics like streak freezes. Additionally, he highlights the impact of minor changes in copy and outlines Duolingo's internal processes for running and analyzing a high volume of experiments effectively. Overall, the episode illustrates the significance of grasping user psychology, conducting thorough testing, and continuously refining features while keeping a sharp focus on essential business metrics.