Your first point, I'm not sure that is true. If you are using a functional style in a language that supports side effects, its still pretty easy to debug. you c

Your first point, I'm not sure that is true. If you are using a functional style in a language that supports side effects, its still pretty easy to debug. you could implement a tap function that console logs the value, then then returns the result of the previous function in the composition/chain. If you are using a lazy evaluated language like Haskell, instead of the stack trace you're used to in an imperative programing language, you'd get the reductions that led up to the reduction of the expression with the breakpoint on it. The second point, However, I do agree with, especially in languages where mutability is the default.