As an artist I can very much say that seeing your rating on a piece go from 5 to 1 from multiple people, is troublesome. No, not because I'm thinking "Oh shit, my art sucks." More of because, "oh no, they think it sucks but they didn't leave a review, they didn't tell me why the don't like it.
I in no way post in the art portal to try and be the best artist on Newgrounds, because I definitely am not, by far. I post my art to get critiqued by you great people, and sure, a nice voting always helps my self esteem, but thats beyond the point. So, if you spend the little time it takes to tell me what you think about the piece, I'll definitely spend the time to read it.
-Love you guys.
InsertFunnyUserName
Try the review request club. They usually deliver.