My son points out to me...
Scar killed Simba's dad.
Sorry for the spoiler.
Keep your enemies close... but not too close.
Loyalties.
Scar wanted the position that he felt he deserved.
Once he got power, he didn't have the skills to be a leader.
Strike while the iron is hot?
Loyalty can be a misguided fool.
Chaos agents play on the disruption caused - the status quo only suits those who are content.
Discontent people want chaos, churn up the waters.
While the waters are murky, lack of clarity allows for usurpers to, umm - usurp.
Crazy moments.
Fear, shark feeding activities and a quick strike, can make for a new regime change.
Loyalty and foresight can stall such a charge into the castle.
Cunning leaders feign weakness to draw out their enemies and provide them with a false sense of security.