In the good old days, storing and archiving sound and picture content was a fairly straightforward task for content providers. As long as their chosen medium was stable and their repository was suitable and safe, they simply labeled the film reel or videotape and then placed it carefully and neatly on an appropriate shelf (usually in their post-production house of choice).
A few notes might have been added — scribbled on a piece of paper — that revealed in more detail what was on a particular piece of content. And those forward-thinking enough within the industry might even have catalogued the library in some fashion. Either way, there on the shelf the content would sit until someone needed to use it again. Once it became less useful, this content would then be moved to long-term storage, somewhere remote but safe, where it was doubtless forgotten about. Easy — job done.
Fast-forward to today’s media landscape, though, and things are quite different, and quite a lot more complicated.