[Terr_]

Closely related, documenting examples of problems or situations the product will not try to help with is also extremely powerful.

You'd think "it does X, Y, Z, and nothing else" would be clear-enough, but in practice a blanket prohibition is too vague to have force, it's an invitation for scope creep. So saying "it will not handle W" is useful, even if it seems redundant at first glance.