[V__]

> "They have a zero-risk policy. It can't be one in a million drives, one in 10 million drives, one in 100 million drives that leaks. It has to be zero."

At some point human error will kick in, a firmware bug will prevent a complete override of the disk, or some new technology will be able to detect overridden data.

[hallgrimur1471]

Yes but shredding the drives isn't zero risk either. For example, there is a risk a disk would be stolen before it reaches the shredding place.

[pixl97]

So measure the risk probability and show it to me?

There are multiple ways to shred. When you get drives from the bank, they have a semi down in the parking lot doing it on site. Other companies tag each device then document each one getting tossed in the shredder. If one of these devices shows back up after destruction then there is going to be some legal hell to pay.

It's nearly impossible to tell if a disk has been erased by looking at it from the outside. But a shredded device, well that's easy enough.