Imagine if you lost every file of your website in 10 minutes and cannot even open the homepage. Would you be able then to recover your data from a backup, or would you spend the next several days trying to get all of the information from your provider?

A wide range of different reasons can cause data lost and not all are things you can control - your site may break, or be hacked or you may decide to move it to a new server. And your data really isn't safe unless you're backing up properly and with lots of redundancy.