So if the post has too much -1s, then a moderator will get automatically notified.
Why a mod should get notified when a post is -1? We need a "thanks" button not a "like" button. This is not a social network (like facebook, and others) it is a forum.
If you want report a post to a staff member, you should use the "report to moderator" function (at the right of each post here in the forum).
This may not be a “social network”, but I bet people socialize anyway. Also, the reason I still think a Like button is better than a Thanks button is because most of the time you like a post (maybe it's an opinion you agree with, or a joke, or an interesting article, or something else), but don't necessarily feel thankful for that.