Tell me about a pattern you spotted across customers that changed how your team worked.

Two things get scored and candidates usually only bring the first. Building the reusable thing is the easy half, and an answer that ends at 'so I wrote a library' has described a side project rather than a change in how a team works. The half that matters is adoption: who else used it, why they trusted it, and what it cost you to get there. The second signal is restraint, because generalizing from two customers produces a framework that fits neither, and a candidate who says what they deliberately did NOT abstract is showing judgment the rest of the answer cannot demonstrate.