Not many people test their backups. I've encountered some situations where the backups didn't work. And one previous employer who was so lazy that he didn't rotate the backup tapes so that the one tape cartridge was used so long that the oxide layer was rubbed off of the tape - so it was no longer brown but was transparent instead (imagine adhesive tape with no adhesive).
alt Hacker News
Not many people test their backups. I've encountered some situations where the backups didn't work. And one previous employer who was so lazy that he didn't rotate the backup tapes so that the one tape cartridge was used so long that the oxide layer was rubbed off of the tape - so it was no longer brown but was transparent instead (imagine adhesive tape with no adhesive).