10 - Masterpiece. Essential to watch. Among the best of what I've seen. As close to perfect as far as I am aware of. Something that I could recommend to absolutely anyone who is interested in the slightest. Could go down over time, but not by much.
9 - Superb. Nothing much in the way of flaws. Chances are I either love this and would totally watch it again; or I think it is brilliant, but way too depressing to watch again.
8- Great. Highly enjoyable and can probably recommend to anyone who is interested. I may or may not love it, but I can definitely appreciate it, for what it does well.
7 - Good. Something enjoyable, but has enough flaws to distinguish itself from being great. Perhaps it is lacking a few things. It might even be worth re-watching, because it still could be fun.
6 - Fair. Still relatively enjoyable, but probably not worth re-watching. Has a few things going for it that keep it from being completely bland.
5 - Mediocre. Has its moments, but either has way too many issues to be fun or I did not appreciate it much. Probably a boring show. Has potential to almost be fair. Borderline decent.
4 - Poor. Probably has a garbage story, plot, and characters; but may be pretty to look at.
3 - Bad. Not worth anyone's time, unless you are masochistic in some kind of sense.
2 - Terrible. Probably really bad for your health at this point. Something that is offensively bad, and not in a fun or entertaining way whatsoever.
1 - Is it even possible to be this horrible? I guess I'll find out someday.