At one of my employers, we did this with backups. Every now and then one of the team was asked to claim to have accidentally removed some files, asking the sysa

At one of my employers, we did this with backups. Every now and then one of the team was asked to claim to have accidentally removed some files, asking the sysadmins to recover them. This was a regular sanity check that to confirm that incremental backups were working. We have self-service backup restores for user files, so we get to spot check which users can be bothered to read the documentation on the wiki...