Why does the world have cheaters and un-loyal people?

First off, all humans cheat. atleast once. on tests or on a person. they dont really have to "cheat" but they can be attracted. every human has attraction to another. even if they have a partner. and of course; they do love their partner too.

That is the way of life. Cheaters cheat because to make life easier for them through the hard obstacles in life (like cheating on tests and stuff), un-loyal people do not want to keep the promises they made to other people, but this is life. The world has cheaters and unloyal people, because it is the cheaters and unloyal people who make that choice, but yah. : D