We ran into this around the admin dashboard during a Friday deploy. The work was mostly unblocking other people, not closing my own tickets. Clear noes protected the roadmap more than extra hours. Writing the doc nobody wanted still changed how fast the team moved. Impact was hard to see until a project stalled without that context. I am still learning to describe that work without vanity metrics.
I used to think more indexes always meant faster queries. Production taught me about write amplification and table bloat instead. We had three indexes that nothing queried, slowing every insert. EXPLAIN ANALYZE finally showed which plans actually used which indexes. After dropping the dead ones, writes got healthier without hurting reads. Now I review unused indexes in the same ritual as reviewing slow queries.
No spike in CPU. Error budgets looked fine at a glance. Users still reported blank pages in a thin slice of traffic. Logs only showed upstream resets with no clear application exception. The culprit was a stale keep-alive timeout between nginx and the app. Aligning idle timeouts stopped the intermittent 502s within an hour. We also added a dashboard for upstream reset reasons so the next page is faster.