"Virtuous" and "vicious" cycles both refer to positive feedback, and differ only in value judgement they imply, so arguably the value judgement is the entire point of using these terms. I can't think of a common use term for negative feedback off the top of my head.
> I can't think of a common use term for negative feedback off the top of my head.
"self-defeating"?
And "self-limiting", maybe, for a "bad" value judgement.
And in general, I think basics of feedback loops should be taught in primary school. I am scared by the fact so many regular people don't comprehend these basic concepts (which is often evident in discussions, when you see people missing obvious consequences of their ideas because they don't get the concept of feedback).