Session length is easy to count, but it is rarely enough to describe quality. A long session could represent deep engagement, repeated failure or a person who simply put their phone down. Quality begins with the purpose of the journey.
Start with intent, not duration
Define the job a person is trying to complete: compare an option, submit a claim, make a payment or understand an account change. Then identify visible signs of progress. A quality session moves toward that intent with proportionate effort.
Include effort and recovery
Repeated taps, reversals, validation errors and long pauses can indicate effort, but no single event proves frustration. Review patterns together and sample the surrounding session. Recovery also matters: an error followed by confident completion is different from an error followed by abandonment.
Make the score explainable
A useful model should let a product manager explain why a session received its classification. Keep the underlying components visible and monitor them separately. The goal is not one magical number; it is a shared language for experience quality.