What makes mean girl be mean?
Ive always just wondered
Popularity, raised, issues in life, thinks better than everyone else..
Jealousy and general b****yness...
It's a million years of evolution, they must compete for a male to reproduce with and will destroy any competition.
When something is going on in there life that is unsettling them and feel the need to make other people feel bad or they get populate and all the attention gets to them and think they are the best!
Their bras are too tight ;) joking... I think they aren't happy with themselves so they project that misery outward and onto others.