Comment by freedomben

This is an important point with biometrics that most people don't realize. When I say that biometrics aren't good security, most people are perplexed because they have seen movies and such that are high-tech where iris scans or fingerprints are the pinnacle of security.

I like to tell them this story that I read somewhere a decade or so ago. It might not be a true story (I never checked) but it's a helpful way of thinking about it.

Bob landed a great job and decided to celebrate by buying a new luxury car (a BMW in my recollection, but could be wrong) that had a thumbprint authentication for unlocking and for starting it, so you never have to carry external keys. One day a thief decided to steal Bob's car. They broke in to his house and tied him up. When they demanded the keys and he said there weren't any, they decided to cut off his thumb and use it as the key. Now Bob has no thumb and his car still got stolen.