Who governs is important because we feel their decisions will impact us. Interesting. . . To what end is important because it affects the degree to which government impacts our lives. Power, authority, legitimacy, etc.
Democracies breed legitimacy.
Viewed as being proper, lawful, and entitled to obedience. I'll give you the stick if you do what I say. I am with the government, an organization that you recognize as an authority, therefore I have power. Affiliation with an organization with power gives an individual power. Government is democratic if part or all of citizens take part in and hold office.