That's an opinion, and not nessescarily a real answer.
That happens a good deal of the time sure. Other times are up to the faction in question. I know of a few who operate factions with varying degrees of trust, dependant on how they operate. Some switch every few days to give certain people equal power, in theory. And sometimes there's the kind of emergencies that require a leader to hop factions for a few minutes before returning.
It all depends on the people involved, really.
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