my top 5 isn't in order....if it's a nice anime i'll watch it with pleasure...and almost all of the animes i've watched were nice. there are also some exceptions like: sweet valerians, kyoro-chan which isn't here but it's also annoying, six angels and some other :) - 1001 night, belladonna etc.
my biggest defect is that i always hope it will get better so i watch it till the end. I really have to learn to cope with being dissapointed with some animes. if it starts bad...it will most likely be bad till the end.