Formula
Bug reports submitted / Active users x 1000
How to measure
Divide the count of bug reports logged in the period by the count of active users, typically expressed per thousand users for readability.
Why track it
A rising bug report rate is often the earliest signal of a quality regression, well before it shows up in churn or satisfaction metrics.
Example
A team notices bug report rate doubling after a release, prompting a rollback before the issue affects retention.