Encryption: Did it work?

[MacBH928]

I have an older HDD(not SSD) that I want to erase whats in it. I was told that once I encrypted it with a password no one can unlock it. So I erased everything, set as new, and chose APFS for format and chose Encrypted. Everything worked fine. Is it encrypted now? thats it, its locked?

I was told encryption takes a long time, and Filevault continue to work for hours in the background to encrypt your local drive. This literally took few seconds, no more than setting up a new USB thumb drive.

 

[MevetS]

Well, if you erased everything on the drive there would be nothing to encrypt. So the encryption process wouldn’t take all that long.

 

[Runs For Fun]

Filevault can take a long time because it has to encrypt the existing data in place. You encrypted the drive during the format operation so it's basically instant.