Self recursion is only a particular case and you can often represent it with loops or folding patterns as you are imagining. However, the really cool use for ta

Self recursion is only a particular case and you can often represent it with loops or folding patterns as you are imagining. However, the really cool use for tail call elimination is when you are calling other functions since you can't rewrite the code without breaking encapsulation. Out of the top of my head, one important example of this would be continuation passing style (you need TCO to turn the continuations into real "gotos")