False reject rate is a statistic used to measure biometric performance when operating in the verification task and it usually calculated as the percentage of times the system produces a false reject. A false reject occurs when an individual is not matched to their own existing biometric template. For example: John claims to be John, but the system incorrectly denies the verification. This can be particularly frustrating for an end user who knows that they are enrolled in the system and should be recognized and verified, but for some reason the system is incorrectly rejecting their scan. This can cause unnecessary logjams, affect service, frustrate staff and negatively impact productivity.