Is Failure to Enroll a typical problem for a biometric system?
Every biometric feature can occasionally or permanently fail. Examples of temporary failures can be caused by worn down or sticky fingertips for Finger Prints, medicine intake in iris identification (Atropin), hoarseness in voice recognition, or a broken arm affecting one’s signature. Well known permanent failures are, for example, cataract, which makes retina identification impossible, or rare skin diseases which permanently destroy a Finger Print . Therefore, every biometric system needs a fall-back process. One also needs a fall-back if a key is lost or a PIN is forgotten; so not only are biometric systems affected by user failure, rather all authentication systems. In fact one can see that also here, biometric systems are preferable to conventional methods.