When you consider the programmers, the bankers and assistant bankers, the police and their clerks, I wonder how many people in the US alone are workers in the identification industry. It is my voice mail, my tax return, my wallet but I can't get them opened or accepted or returned to me unless I can identify myself as me. I really am me but it is not easy to convince others of that.
Say I want to open my email. I need to use my password. What is my password, anyway? Or, I could call you up. You recognize my voice, right? Oh, I have a cold and that is why I sound funny. Yes, I have aged since we last met and I have shrunk. So, yes, I am wrinkled and little but honest, it is still me, the guy who took pictures of people with you on the boardwalk that summer. Yes, it is really me, the guy who worked for - what was his name? Sammy, was it?
There are various steps I can take. I can call your brother who has known me for a long time and try to get him to convince you I am who I say I am. The US government has my fingerprints and they could tell you. We can do the two step, where I enter my password and then get a phone call with a one-use number that I can enter, too. Getting that number on that phone line ought to do it. Nope, must show my fingerprints to the fingerprint machine and my retina to the retina machine and have my voice checked by the voice analyzer. Ok! I am in but access to limited for safety's sake to 90 seconds.