Biometrics have both a high False Acceptance Rate - they will accept invalid input - and a high False Rejection Rate - they will deny valid input. Scanners can

Biometrics have both a high False Acceptance Rate - they will accept invalid input - and a high False Rejection Rate - they will deny valid input. Scanners can be tuned one way or the other, preferring FAR or FRR, but either way, they are kind of unreliable. This is why multi-factor authentication is a thing. Generally, pick two: something you have, something you know, or something you are. If the scanner doesn't like your fingerprint this morning, just use your proximity badge instead, and if someone takes a photo of your fingerprint, it's still useless unless they also know your PIN. The issue is that a lot of our hardware, particularly phones and laptops, is single-factor authentication. And on top of that, this hardware knows the login to a bunch of other very sensitive material, like your bank accounts.