I'm reading a book. Every few pages, in the bottom left margin, it repeats its own title, preceded by an increasing number:
24 The Fellowship of The Ring
What is the point of this? Surely they cannot think that anyone would forget which book they are reading, and are too lazy to flip it around to look at the cover? Is it some sort of copyright protection? Does it somehow, in some way that escapes my mind, prevent some sort of undesirable behaviour? That's usually what things like this end up being, but in this case, I cannot even think of a reason. If somebody copies the entire book, what does it matter if it says the title of the book on every Xth page?
It does not say something like:
(C) 1950 J. R. R. Tolkien. Copying forbidden.