In "How Democracies Die", Levitsky and Ziblatt (2018) argue that today's democracies fall not because of mass protests or dissatisfaction with democratic idea, but because of popularly elected leaders who undermine established democratic norms. In their view democratic backsliding is a complex process which undermines core principles of liberal or full democracy like the separation of powers, the rule of law, the equal protection of civil and political rights and freedom of the press from populist standpoint.
As a result, the crucial question therefore is how to understand democracies that lack some essential elements and face the pressure from populist leaders.