They run an election based on a platform. You are voting for the person and the platform. They aren’t there to do your wishes, but to accomplish their agenda the people “agreed” was the best of all options that election cycle.

Sometimes this agenda is altruistic, like reducing crime. Sometimes it is populist, or social, or even fascist. Even then, elected officials are supposed to have limited power, not unlimited power. In some (many, depending on where you live) cases, they’re not even accountable to the people — the people can’t recall them, to remove them is a political act by other parts of government.