Why do monads not compose in scala

Question

Why do monads not compose when a Monad is an Applicative and an Applicative is a Functor. You see this inheritance chain in many articles on the web ( Which i have gone thro

Answer 1

Tony Morris gave a talk on monad transformers that explains this precise issue very well.

http://tonymorris.github.io/blog/posts/monad-transformers/

He uses haskell, but the examples are easily translatable to scala.