Imagine someone buys the book and after finishing it they are like, “wait, where are the remaining 10 100 832 facts?”
It mentions something like that in the introduction. It's like a choose your own adventure kind of book. There are also Easter eggs that no other chapters point to, so you have to find them in a different way. It also says you'll sometimes reach a dead end, in which case you'll have to backtrack and choose a different path. There are also subroutine chapters that end with a return instead of a list of next chapters.