Pretty sure you misinterpreted what OP meant by "power". Sure Bush left office when his term ended, but Obama continued a lot of the policies we thought were going to be ended, keeping the NSA in a greater position of power than it should be. That's the power that hasn't been relinquished.

> If the people in office get voted out, they leave. If they didn't, we might have a problem.

No, as evidenced by the our current situation, we still have a problem.