Yeah, sure, a higher kinded type here, syntax sugar for generalized computation side effects there, and before you know it you're neckdeep in monad transformers

Yeah, sure, a higher kinded type here, syntax sugar for generalized computation side effects there, and before you know it you're neckdeep in monad transformers and your head rapidly decompresses in a combinatorial explosion every time you try to do a new thing and users need to remember seven different type parameters to read a line from stdin. :(