Replying to What is the point of karma?

What is the point of karma? I until about 4 or 5 days ago had a rating of around 2600. And in one day I went from a 10.00 to a rating of 6.67! How is that even possible? And now my score is all the way down to 1911! I posted one video, which I don't think is bad.. And all of the sudden my Karma shots down? I know that I'm not a professional or anything, but why such negativity? Rather than just down voting and ruining my karma, Could you at least let me know who I could improve in a comment or something? What the Hell?