Democracy is ingrained in our DNA, because it has helped us to survive. We have lived for most of our evolutionary history in small bands, and this has shaped our psychology today. Upstarts would occasionally try and dominate others — dominance is part of our primate heritage — but our ancestors had a number of effective means to keep these irritants under control. Traditional societies still use these techniques – we call them STOPS or strategies to overcome the powerful — with much success. The most effective weapon that a group can deploy is to desertion, by simply leaving a dominating leader behind.
Not only do we naturally organize ourselves into democracies but we are a social species – and disaffection is contagious.