As an OCaml beginner my understanding is that I can do away with needing to understand monadic IO (yet) because OCaml is non-lazy and allows side-effects. I also like monadic parser combinators because they'll allow me to write parsers without the tedium of recursive descent, or being reliant upon parser generators. I have a rough understanding of monads as a purely algebraic abstraction (https://arcanesentiment.blogspot.in/2017/06/purely-algebraic...) and an even vaguer idea as a "representation of computations as values", based on this excellent thread: https://discuss.ocaml.org/t/can-monads-help-me-my-refactor-c...
But I don't grok it yet, which I'm sure I'll be able to once I find an occasion to use it. I suspect I'll hit that point sooner if I were using Haskell than OCaml though. I'm still collecting analogies (burritos, boxes, "smart pipes") and I want more. If nothing else, it is fun, and contrary to popular opinion, I don't think it distracts me from its essentially abstract nature.