Refresh Backup data

[AAA]

Hi,
Question:
FreeFileSync compares backup data with the original data but as far as i can tell unchanged backup data will not be refreshed.
What do you think, is it required to copy the backupped data entirely once in a (long) while?
Does it matter what kind of backup media, HDD, DDS, ...?
And does it matter if backup media is online only occasionally?

[xCSxXenon]

I see no reason to re-copy data if it is unchanged. If your data is becoming unusable from just sitting there, you should replace the backup media. The shelf life of modern storage is so long that it will suffer from a mechanical/physical failure before the written data gets corrupted from radiant forces. Most importantly, you should have multiple backups, hard drives are cheap

[AAA]

Thank you for your comments and recommendation. I wasn't aware of the long life times of these cheap storage's.
Of course we have several backups in regular intervals: Weekly, Monthly and Yearly; and both online and offline.
I was mainly concerned for my Yearly backups on SSD.

[Plerry]

... I was mainly concerned for my Yearly backups on SSD.

Why on earth would you make backups (even more: yearly backups) on an expensive medium like SSD? SSD is particularly suitable for fast and frequent reading, something you do hardly or not benefit from when using SSD for backup purposes.

[AAA]

Because they are fast, not mechanical and no extra power required.

[Plerry]

All of which is irrelevant when used for (at least less frequent) backup purposes (assuming you let HDs hibernate in between backups).