Discovery: the one I got wrong
At eXp, the Director of Transactions and the Director of Agent Operations came to me together with a vague ask: we need a way to keep agents connected, and it has to live in our enterprise system. From that I created ConnectID: flexible groups outside the official contractual team structure, built in Mendix, where anybody could look up what a given Connect ID was for.
It was well architected for what was asked, and the demo landed great. A month after launch, two groups had moved over while dozens of teams were still coming in on spreadsheets. The real requirement was hidden under the feature asks: leadership was afraid of losing the incoming teams, and the tracking spreadsheets were failing audits.
A sharper product with fewer bells and whistles, wired into onboarding and compliance, would have delivered exactly what they were looking for. I consider it a failure I own, even though it shipped and looked like a delivery, because navigating to the truth of the ask was my job. If I had been a better product manager at the time, I would have found the real pain sooner. Now I go find it first.