The convention is that the text on the spine is right-side up on any volume that is more than about an inch and a half wide (like a dictionary or a Bible), otherwise the title should be oriented from top to bottom in such a way that if the book is lying flat with the cover facing up then the text on the spine is right side up.
It boggles my mind that there are people who have been entrusted with book cover/media packaging design who don’t understand this simple concept. Get it together, people.
