Its a great feature. I have a ledger nano S. It looks like a big USB key, so it would be really easy to lose. Or it could break or malfunction or get stolen or something. I don't want to risk a significant chunk of my assets on the off chance that happens, so I store the recovery keys in a safe place as a backup.

Now, given that I have recovery keys stored in a safe place anyway, the ledger itself is somewhat disposable. Its still a great way to actually access my money, but if something happens to it I can just get a new ledger. So, yes, I want it to wipe itself if the wrong PIN is entered a few times. That feature means if I lose the ledger I can relax knowing my money is still safe even if somebody finds it.

Usually you have a group of "recovery phrases" that once entered into the device, it restores itself so you can still access the funds. There is more information how this works on a Ledger Nano S for example here: https://medium.com/@trionkidnapper/ledger-nano-s-restoring-a...

> Now that seems like a really shitty security feature. Whoever finds it can just wipe out your funds?

That is good for someone who have several secure redundant copies.

No, they wipe out that hardware. It's like your smartphone wiping itself with a few wrong password attempts. It can still be recovered, it just means that particular hardware is now useless until it has been recovered. It's great if you lose your smartphone, but if it was just your kid messing around then you can still recover it.

They can only wipe out your funds if they copy they wipe is the only copy. But this is extremely poor practice, and backups are very common practice to protect against precisely this sort of thing.