This perhaps is a reference to the french writer Tocqueville and what he referred to in his writings Democracy in America as the Tyranny of the Majority. Democracy's borders change based on majority opinion at the time. You have to test those to see if the majority will go along.
A democracy is a tyranny, only instead of a dictator there are many individuals who determine what the borders should be. Democracy is not good because the minority will end up being abused and mistreated to the benefit of the many. A good illustration of a pure democracy is: there are 4 people in a room, 3 are men and 1 is a woman. The men vote to take advantage of the women sexually, she votes against it, but she loses, because this is a democracy. A representative republic like we have here, or at least started out as, in the US works well for all people because all can benefit as a whole, not a small segment who have power.