If you grew up in the 80s/90s and remember what cassette tape covers looked like, it might shock you to learn that major record labels in the 70s had absolutely no clue what to do with this new format. They were terrified of cropping the art, so...lets just slap it on white.

Maybe we should put some marketing words on there, so it doesn't look so plain? Oh hey, we could add some key songs, even though the full track list is on back.

In the early '80s they started adding a black bar with some text, which at least gave the design an intentional look. I remember seeing a few of these mixed in with "regular" covers in the late '80s.