This isn't going to get everything right, but it's something I've been wondering for a while. Please think about it and answer as honestly as you can.<p>I usually upvote a submission because I...
<i>other (comment)</i><p>The article is interesting, intellectually stimulating, teaches me something I don't know, teaches something to others that they should know, "engaging," or unexpected in a positive way. I actually think all of the other answers are not good and contrary to the spirit the forum is trying to cultivate.
I upvote a submitted article if I think the submission says something important (at least thought-provoking, and possibly unknown to most people here) that will help hackers do their business ventures and their personal living better.
A major factor is repetition - if I saw the same topic (even if a bit different article) on the first/second page yesterday, then I definitely won't upvote.
In rare cases, I'll upvote an article that I think is sub-par (poorly written, logically flawed, a bit off-topic, previously posted, etc.) just because I think it might provoke an interesting discussion. In many cases, the comments here make much more interesting reading than the articles.
Sometimes I up vote a couple of submissions following one I would want to down vote, but since there is no down vote, we can only try to up vote relatively all the others.
Each of my upvotes probably breaks down to:<p>10% - A digital thumbs-up to the author.<p>20% - I feel like I gained something from the article and I want to repay the author by promoting his work.<p>30% - I want other people to see it because the world would be better if more people knew about the subject of the article.<p>40% - Fulfilling a narcissistic craving to express my approval of something similar to a Facebook Like or Youtube Thumbs-Up.<p>It gets interesting when the link is, for example, a raffle. I want to upvote because of the first, second and last reasons but I want to downvote so that less people hear about it thus increasing my own chance of winning. Individualism vs collectivism encapsulated in a single mouse click.