All of it makes much more sense if you use Haskell more. For example, when you're trying to write some program that works in an inherently stateful fashion, as

All of it makes much more sense if you use Haskell more. For example, when you're trying to write some program that works in an inherently stateful fashion, as a beginner you usually pass state as an additional argument to your function, and return it as additional result. Then, when you learn about State monad, everything clicks into place.