Well, yes this is kinda true, but comments help and the ability for others to edit your answer if they have enough karma also helps. Plus a ton of people update

Well, yes this is kinda true, but comments help and the ability for others to edit your answer if they have enough karma also helps. Plus a ton of people update their answers to say "Update: My answer was once the right one, but in Python 3.3+ there is a better answer by Michelle below." What would be cool is if StackOverflow let you choose to move your question down in the ranking to be below someone else. That way the history of the answers is still there, but the more update answer would get the first impression.