I just go by default backup. Therefore, after reinstalling Ubuntu 12.04, I restored the backup, expecting megabytes of LibreOffice Writer files to show up on my desktop. They never appeared after restoring successfully. Did I just wasted my entire work on misunderstanding on what Backup really is?
You need to specify what directory's you want to backup. Make sure you back up your home directory and etc. This will hopefully cover all your config files and then personal files and documents in your home.
In BackupYourSystem on help.ubuntu.com you find the Ubuntu backup page. It contains lots of information on backups and the different software packages.
Did I just wasted my entire work on misunderstanding on what Backup really is?
No you are correct - thats what a backup will do restore files. But in Deja Dup, the default backup suite, you need to make sure you select the directories/partition that you would like to backup. If you didn’t backup the desktop then you will have lost all of those files.