Digital Journal Negative Marked Comments

I have noticed in the last few days that a lot more comments are getting negative marks. What types of comments should get a 'thumbs down'?

I know when I write an article on Digital Journal I enjoy getting feedback. Whether the reader agrees with me or not, it is nice to know that people are taking the time to comment. Some people comments are not very long, short and to the point, but you can tell that they have read what was written and taken the time to write about it. I am not understanding why the comments are getting the down arrows unless I am misunderstanding what "this comment seriously lacks content and/or original thought." is intended to mean. If a comment of 'cool' or 'great story' is marked down I can understand. I would hate for this to keep people from posting comments.Am I missing something?