Simple definition
Mean Time Between Failures measures the average operating time between failures of a repairable component or system.
Purpose and use
MTBF, Mean Time Between Failures, describes average operating time between observed failures of a repairable system.
How does it work?
It generally divides the selected operating time by the number of qualified failures in the observation period.
Example and verification
Before comparison, verify comparable equipment, observation duration and failure definitions.
Points to watch
An average does not predict the next failure date. A period without failure proves neither infinite reliability nor a well-established statistical rate.
In short
Report MTBF with its scope, event count and observation limits.