x7x_

Why do we have public property if not to use it?

Or should we divvy up all the public property to the highest bidders?

Can you explain why they would be 100% safe?

For traditional HDDs, the sectors holding data can only have one charge. Changing it doesn't leave much of a history of what it was (either it's 0 or it's 1). Maybe trace fields, but nothing of note (i.e. charge is 0.999999998 instead of 1), and you'd be hard pressed to be able to make anything out of it even if you could read it.

Combine an overwrite with a hammer, and you're for sure 100% safe though.

As for the SSD or flash, I've no clue :P

Could ssd/hdd manufacturers have code on their firmware or somewhere else that could help lie and make you think data is actually gone?

Technically possible, but when the manufacturer gets caught implementing it, it'll be a shitstorm for PR. The only logical reason I could see this being implemented is a honeypot-type scenario or a malicious user purposefully implementing it to smuggle data (see i wiped this drive, here's the log, see ya).

No, you're thinking of that movie with Cary Elwes and Andre the Giant.

So you would not have done what Hillary did with her emails?

Since you know, she technically didn't own anything in that email account and all, being a public servant.