Comment by Kon-Peki

The birthdate in my SSA master record was wrong, and I discovered it only because the IRS upgraded their security (~10 years ago) and I could no longer file my taxes electronically - I couldn’t make it past the anti-fraud checks.

It took something like 2 years to track down the root cause (the SSA master record); the value they had stored looked a lot like a fat finger job by some data entry clerk back in the 1970s when I was born.

Fixing it took about 30 seconds at an actual SSA office building. I spent more time in the elevator.

Assuming everything in a computer is either correct or fraud is a terrible assumption when you are dealing with hundreds of millions of people in the real world.