We collect data of your voting habits and sell it to the highest bidder. What else would we do? Haven't you noticed that ads you're seeing are chosen based on your votes?
Ah, yes, that explains it......

And yes, I up-voted this comment because it is witty and original.....
Downvoting doesn't explain why you disagree with a post. Is the content not factual? Is there a better solution? Does the solution posted not work? Or do you just have some issue with the poster, that you're expressing by downvoting? An explanation is appropriate.
Voting for any post, up or down, should be based on the merits of the post, and not the poster. You may dislike someone, but that doesn't mean that everything they post is wrong. Likewise, you may like someone, but that doesn't mean everything they post is right.
With that in mind, upvoting a post based on its merits requires no further explanation. Downvoting a post based on its merits does.
I agree that since not everyone votes based on a post's content, the vote buttons should be removed completely, which will force people to justify their position by communicating.
Agree completely with this. (And, yes, I up-voted these posts).
In essence, an up-vote is usually an expression of agreement or approval or the poster/argument/opinion and, unless the up-voter wished to elucidate or clarify or support more strongly on his or her up-vote, nothing more need usually be said.
It is different with a down vote. It is not just that it expresses disagreement (with a poster/opinion/viewpoint/fact/factoid/perspective), it is that it allowed posters to do so safely, hidden behind the cloak of anonymity of the net.
By allowing down-votes without having to offer a clarification, or merely obliging posters to state "I disagree" when clicking that down arrow, or, without having to offer an explanation, or justification for them, allowed - to my mind - a negative, nihilistic and downright unpleasant atmosphere to develop or emerge on some threads, and, I for one, am glad to see that it has been removed. In essence, it allowed for easy, and lazy negativity.
I don't understand this.
If I have to explain a down-vote why don't I have to explain an up-vote?
The same rule should apply to both.
It is better for debate if you have to explain both, but sometimes an up-vote denotes agreement (which does not often require further explanation, especially if one is expressing agreement with something which has already been said), but it is better - in my view - to require that reasons - if any - for a no-vote be expressed and articulated.
I agree that both can require an explanation some of the time. I disagree that a downvote never needs an explanation.
Now, see how much more information was exchanged by you voicing your disagreement, rather than simply clicking a downvote button? That illustrates my point perfectly.
Agree.
I say bring back the down vote button. It wasn't hurting anyone.
Actually, unfortunately, it was when it was abused, as it was in some threads.
I think it is something to do with the perception of safe personal space and how differences/disagreement/dissent are subsequently expressed. The internet allows for a far greater degree of personal distance, (and presumed safety) which, in turn, allows for a more hostile tone to be taken in the expression of difference/disagreement than, if, for example, one was to express such disagreements face to face.