We were recently apporached by a non-profit site that runs on Drupal.
Their major complaint was that the "content on the site does not show up". The other main complain is that the site is very slow.
Everyone needs to have a backup plan for their live site. Not only can your server's disk get corrupted, but you can also erroneously overwrite your site with bad code or bad data, or your site can get hacked.