I typically use the karma button to express that I think the comment is generally good or generally bad, and the second button when I want to send a more nuanced signal—for example, if I disagree with your opinion, but there is nothing wrong about the fact that you wrote it, that would be “×”.
My opinion is that the “lazy” upvote/downvote system is useful, because the more costly you make it, instead of voting more carefully, most people will simply vote less.
I typically use the karma button to express that I think the comment is generally good or generally bad, and the second button when I want to send a more nuanced signal—for example, if I disagree with your opinion, but there is nothing wrong about the fact that you wrote it, that would be “×”.
My opinion is that the “lazy” upvote/downvote system is useful, because the more costly you make it, instead of voting more carefully, most people will simply vote less.