And like in most cases, when you're in power a long time, you're going to see corruption. And the cyclical nature of the mandate of heaven says that eventually when that corruption comes you're going to have revolt. You're going to have the gods putting down natural disasters. You're going to have invasions because you're not doing the right thing. And that this loss of the mandate of heaven gives the people the right to rebel. It justifies rebellion. And that eventually through these revolutions you're going to have a new dynasty which is going to bring peace and order.