Now there's the whole conversation around monads that carry no value intentionally throughout the entire monad. So, for example, if the monad type is 'Quark' the the monadic inhabited types are up, down, strange, charmed, top and bottom, and their values are ... nothing at all: their instance is the value, it has no underlying value it carries (unless you want to get into the guts of spin and charge ...), its the particular monad instance, or the particular quark, we care about, not what's inside at all, something like monads as enumerated values, but ... eh. Monads-as-burritos is a limited view, it will trip you up, but for the most part it works. When you do get to the point of treating monads-as-monads, and not caring, anymore, about the underlying value, you can tap yourself on the shoulder with monadic-Nirvana. It's a really good feeling, and gives an entirely new understanding of monads and their utility. "Good to know," as it were, but monad-as-burrito works for the most part and is tasty, too, to boot.