When you manage a site, having a backup is something quite necessary, especially if you have important information or you have invested money and time in developing the website. There are numerous scenarios why you could need a backup - if you update a script and something breaks down, if you eliminate a file or a whole folder by mistake, and so on. Having regular backups will help you avoid any loss of information or at least minimize the damage, which is still better than losing the entire site. You may download a copy of your content on your PC occasionally, but because you cannot do that after each and every change, you have to rely on the backups which your hosting provider generates. Because that's something very vital, you have to make certain that they keep up-to-date backups, because a backup generated once every one or two weeks will not do any good in case you run a website such as an online store or a holiday accommodation booking site.