I feel like this answer will be super obvious, but I'm unable to find an answer in Civi's documents. I feel like the campaign status sums up the state of the campaign so I'm just wondering what info the active / disabled fields capture.
This is so that you can temporarily or permanently remove a campaign from being selected. If you have say 30 campaigns and 20 of them are completed, you don't really want them cluttering up the drop down lists when you create events etc. You only want the active campaigns.