People make mistakes. We are humans - just like you, forgive us. I know it's been discussed here before, but I suggest a different approach.
Sometimes I up/down vote an answer because I believe it's right/wrong and the question asker should look/not look at it.
When someone posts an incorrect answer and gets voted up, some other user who detects this mistake will add a comment, explaining why this answer is not to be followed. Then I read that comment and understand that I have made a mistake as well following the answer and upvoting it (same goes for the opposite - down-voted correct answer).
My request - Include comments as a 'post edited' status - because sometimes even the original answerer posted a comment.