I came across this SO meta Q titled:Should the weight of downvotes be increased? that I believe Jeff Atwood asked. It ultimately got declined and was wondering if anyone knew the back story as to what happened and why it was declined.
I don't have the answer but I do have an opinion (TL;DR -> Positive reinforcement is a better motivator than fear of punishment). It's interesting that:
When we started Stack Overflow, we wanted to make sure that downvotes were more of a visual and psychological motivator than a punitive action.
That seems like a wise choice to me, because it emphasizes that what's significant is the question's score, not how many points it did or did not generate for the user. The critique that:
downvotes don't quite carry enough... -5 downvotes and +1 upvote (for sympathy) yields zero points overall
Sort of turns this on its head and implies that what's most important is the number under your name. Of course, it's somewhat important, which is why this is even a question, but it should not be the ground of the whole scheme.
Right now your user cred is mostly about people giving (or not giving) you points. If the game became more about people taking points, my feeling is this would just attract more negative behavior, grudges, etc.1 It's one thing to be told you are wrong, it's another thing entirely for someone else to be able to arbitrarily penalize you for it.
Also, I don't want to be a cop, and if I knew that someone might be sitting there going, "Oh that sucks my points are down", then I would be less inclined to down vote -- I'm already disinclined as it is. I don't want to punish people, I just want to draw their attention to their mistakes. Consider on U&L:
goldilocks upvotes cast 658 down 24 slm upvotes cast 5831 down 104
Looks like I'm relatively stingy, :( hmmm...food for thought...better get out there and vote...anyway, I imagine what would happen if you changed the penalty would be some people would downvote less and some other people would downvote more. Betcha. Would that be better?
Finally, downvotes should reflect more on the anwser/question than the answerer/questioner, which they do. Again, gaining points is what creates the game and encourages us to try and do a good job of it, but losing points can only discourage people from trying.
1 As is, making the penalty minor and including a small cost to the downvoter probably discourages "retribution votes". If downvotes were more serious affronts to the user, you'd see more people getting serious about retribution.