The reason is, people are more likely to both view and comment on something made by a person they know. When someone new to the site posts, they are unknown, so people are unfamiliar with them, as well as no history of works to see their progression. I just deal with vectors, so even though I try to view most, if not all of the large art work, I only really post on the ones that I can give good critique. As some people have seen, when it is about a vector, I can write a paragraph without meaning too, but that is because it is what I know. Sorry I can't help for you in this situation, but maybe PM a few people of works you like on here, and ask them to give you some critique, then I am sure more people will follow.