SUMMARY: A measure of completed work describes a selected population. It does not automatically describe the experience of everyone who entered the service, particularly those whose cases remain open.
State Who Enters the Calculation
In The Wait Outside the Average, short completed requests produce a reassuring number while a longer unfinished wait remains outside it. The average can be arithmetically correct and still support an overbroad headline.
Specify the starting event, completion event, reporting window and inclusion rules. Requests completed this morning are not necessarily the same group as requests received this morning. Include the sample count so a reader can see the scale of the summary.
Describe Open Work Separately
An open case has an age at a stated observation time, not a known final duration. Present open counts and appropriately chosen age bands alongside completion measures. Consider whether an internal oldest-case review would expose neglected work.
Do not simply mix current open ages with completed durations and label the result an average completion time. That would treat unfinished observations as though their endings were known.
A Different Summary Is Not a Complete Repair
Changing from a mean to a median may change the description of completed cases, but it does not bring excluded open cases into the population. First establish whose experience is represented; then decide which summaries fit the decision.
Age alone also does not explain a delay. A case may be awaiting information, paused under a defined rule or overlooked. Preserve those distinctions and provide accountable review rather than inferring a cause from one number.
Make the View Useful and Proportionate
Public reporting should not expose identities or sensitive case details to demonstrate that a queue exists. Internal follow-up can retain the necessary references under the service’s access and retention rules.
Try Test an Unfinished Wait within the systems accountability guide. This is a conceptual review framework, not a statistical model for predicting completion times or a rule for prioritizing real cases.