How Not to Measure Latency (The P99 Lie) by GIL Tene
youtube.comTried to link to the specific timestamp in the video, where the p99 lie is discussed. Core takeaway for me was that most users of a page will experience the p99 latency of the system: https://youtu.be/lJ8ydIuPFeU?si=HasLt5QBsB1tzww_&t=648