I know the majority of haters are often angry with themselves, the desire to harm others often stems from the desire to harm oneself, hence the murder suicide MO.
So with that said I believe haters are weak, envious, jealous, and down right pathetic people who would rather try and bring someone else down rather than try and build themselves up.
I think that haters are people with just low self esteems. People who make fun of other people just to feel good for once in their miserable lives. Like @Hitmarker (;
The stupid part is they waste so much effort on hating everyone better than themselves they will never get to where those people they envy are, because those people stay focused and motivated.