QoE Target & Diagnosis Checklist

One-page reference to the QoE quartet (video startup time, rebuffering ratio, bitrate delivered, playback failure rate): each metric's plain definition, a rule-of-thumb target, the most likely causes when it degrades, and the honest-measurement traps to avoid (averages that hide failures, QoS-vs-QoE confusion, ad calls inflating startup, bitrate chased at the cost of rebuffering). Includes the slow-start revenue arithmetic.