I think many programmers find it hard because experience with Algol-derived languages give them bad assumptions - they expect all of the conceptual baggage of m

I think many programmers find it hard because experience with Algol-derived languages give them bad assumptions - they expect all of the conceptual baggage of mandatory stack allocation, so recursion seems ludicrous and complicated. Recursive cases in languages with tail-call optimization are like inductive reasoning in mathematics - "How long is a list? If it's empty, zero, otherwise one (for the head) plus however long the rest is."