OPS.15.1:8 - Common Anti-Patterns and How to Avoid Them

Mistake invited by ordinary records	Consequence	Repair
Count one event-subject row as one event	A shared batch or delivery is multiplied.	Count distinct occurrences or the intended subject relations explicitly.
Treat the observation cutoff as completion	Unfinished work receives a false short duration.	Clip its exposure to the window and retain its unresolved endpoint.
Sum overlapping resource intervals	Recorded occupation can exceed possible available time.	Form the union for each resource before calculating its occupied fraction.
Compare internal time after moving admission	A counting change appears as faster customer service.	Include upstream waiting under the unchanged recipient boundary.
Use a mean without its population and weights	Different mixtures masquerade as changed performance.	Reconstruct the aggregate from compatible totals and counts.