forcederrors verified
Forced failures
Messages we failed on purpose, permanently.
In detail
Counts our own interventions rather than the receivers': a forced error with a 5xx code, or a rewrite rule that failed the message. Separating deliberate failures from real ones is exactly what a failure chart needs, and this counter is what makes it possible. A steady non-zero value with nobody remembering why is the signature of a forced error left in place after an incident.