Consider the paradoxical control that some people have over others in families, and formal and informal groups.
I posit the winnowing principle:
First, the abusive person (sociopathic, etc.) forms or achieves power in a group. Those in the group who do not tolerate the attempts at abuse and manipulation (recognizing them as such) will leave the group.
Three kinds of people are left:
1) Those who are like the abusive leader and are joining power;
2) Those who do not yet realize what kind of situation they are in: soon they too will leave.
3) Those who for whatever reason come under the power of the abuser(s).
So if anyone wants to know how the Jim Jones's of the world operate, I believe that this is a good basic behavioral model.