I have seen it many times before and I saw it again yesterday. Backups with nothing on the backup media.
    Making backups is a chore. It is such a chore that most home users don't do it. Many businesses do make regular backups but it is still considered a chore and becomes an automated process, often delegated and most bosses don't want to know, be bothered, or care until something goes wrong. I have seen people cry over lost data, really!
    If you are making backups, you absolutely have to check them regularly to make sure that you are actually backing up the right stuff. Check the dates, current backups should have some files with current dates, not all because there are often files that never change, but some files will have the right dates.
    You never need your backups until you really need them. Don't learn by burning your fingers, take my word for it the stove gets hot!