I rate based on personal enjoyment, which doesn't mean that I overlook animation, OST, characters or plot so expect the top shows in my list to have one or several of this qualities being top notch.
10: Masterpieces/Must watch at some point.
9: Really awesome shows/Favorites.
8: Recommendation material.
7: Good shows, may have some flaws but they're definitely worth watching.
6: Shows that had SOMETHING enjoyable, it could be boring but you can give it a try.
5: Regular stuff, cliché or shows that lost all their potencial at some point.
4: Bad, don't bother.
3: Really bad.
2: Don't even think about it.
1: Troll material.