I mean in a general life sense I completely agree but not when were talking about grading others. Setting the bar for perfection at "exceeds my personal ever-changing expectations by an arbitrary unspecified degree" would actually cause me distress to have to carry out. I could never judge another human being in such a way and I would feel, and have felt, degraded being judged that way.

Like why even set expectations in the first place if your bar for perfect is "impress me"? Why is "I did everything you asked" less than perfect?

Who's talking about perfection? Perfection is like zen -- it's a goal that can never actually be achieved, so there's no problem in not achieving it. Striving for it nonetheless is a good thing.