This almost always happens. Because in order to achieve what they have achieved, they had to give their citizens a certain amount of freedom. Generally when th

This almost always happens. Because in order to achieve what they have achieved, they had to give their citizens a certain amount of freedom. Generally when the new generation becomes old enough , it would have never seen why people are afraid of the rulers so much, then it becomes a situation of a showdown. Though it doesn't always have to end with a bloody outcome, for instance Spain went from dictatorship to democracy quite peacefully after it's dictator died in 1975.