For example, take a look at the season 2 finale. The episode name is not even decided yet and people already give it a 9.4!!
I highly doubt those 100 people had seen those TBA episodes already.
I think i got 3 reason why they do it.
1) read too much spoiler and just rate the episode before it's out.
2) really hate avatar and rate every episode (including TBA) a 1.0
3) a luckly someone got the episodes from the producer and got to watch the episodes early. (possible but not likely in number of hundreds of people)
Boil down
people need to stop rating show before it's out because most of them didn't even watch the episode yet!!
It make me sick to see season 2 finale got a 9.4 rating already because of retarded imbecile rating it.
If you did watch the episodes, i still think it is better off that you hold your vote until the episode is aired. You dont want to be mistaken as a random voter like 90% of the voter there.