The theory of proper government requires development of moral and philosophical concepts that go beyond simple majority rule. A pure democracy usually ends up as five wolves and three sheep deciding what's for supper.

For example, it's obvious to most people that slavery would still be evil no matter how many people voted for it. There are other examples, but most of them are not this clear-cut.

In practice, constructing a working government on this idea is very difficult. The will of the people needs to be part of it, but not to the point where it becomes a tyranny of the majority. The minority must be protected, but not to the point where they paralyze the process. Theorists have lost a lot of hair over the years on problems like this, and worse. You could fill a stadium with the number of theoretical ideas on How To Run A Society. A few of them are even pretty good ones. A very few.

The system the U.S. came up with is a pretty good compromise although of course it still has flaws. Any system of government will, which is why a primary goal is to keep it decentralized, and keep it from accumulating too much power.

Most of our historical misery has resulted from giving human beings the power of gods on Earth.