I remember seeing that some questions are blocked (not sure about the exact wording). Meaning they are not closed but you can't add additional answers.
When does this happens ? Is it discussed here on meta, or is it left to moderators appreciation ?
I'm wondering about that because of this question for which I understand people wanting to close it. But it would be a shame that it gets deleted since it's something any programmer (and other people working with computers) comes up with someday.