The document summarizes the process taken by Duolingo to improve their Stories feature based on user research. It describes how Duolingo conducted interviews and usability testing with both active and lapsed users to identify key pain points. This revealed that Stories content did not connect well to courses, was difficult to use on phones, did not match users' ability levels, and lacked features for practicing or reviewing words. Duolingo prioritized addressing these issues through product and content changes, which led to improved Stories usage over time based on subsequent usage data. The main lessons highlighted are to invest in understanding users, focus on the most impactful insights, prioritize changes realistically, and ensure AB tests are grounded in strong product sense.