How often do you need to double-check the hard drive so that the files are NOT demagnetized?

Question

Backup

I will buy an external portable USB hard drive for backup storage. I will copy the contents of the main working disk to it once every 3 months. And then put it on the shelf.
The following is of interest, if the disk is not used at all, then the data may be demagnetized, while the disk itself will remain working. Well, let's say if the disk is written and stored for 10 years, then the disk will remain working, only the data can be demagnetized. Or maybe not 10 but 20 years. It is asked. How often do you need to do a check on the surface of the disk in order to remagnetize and restore the data.
I understand that in idle mode, the controller tries to double-check and overwrite them there. BUT!, this process can be slow and incomplete. Let's say we have a 4 Terabyte disk. So let's say the controller checks for 5 gigabytes, and then I eject the disk, despite the fact that I will have no idea what the controller has been doing for the last hour.

Answer 1

How often do you need to double-check the hard drive so that the files are NOT demagnetized?

Rechecking won't help.
Rewrite only. The HDD controller itself will not overwrite anything.

With what frequency

And nobody knows.
Some old HDDs that are 20 years old are perfectly readable.
But now technology has stepped far ahead, and the recording density has grown a lot, so modern ones will keep information up to date for who knows how long.
Maybe five years won't last.

Answer 2

Read here .

Infa is read without problems. 20 years, unless of course we are talking about constant inclusion.

Answer 3

My advice is buy an ssd. Better 2. One will survive anyway