Not all of them do. Only the weak ones. They get tempted, go through difficult times, care too much about those around them, have people around them die. Think of President Lincolin. His son died, he was suffered severe depression, he made a great difference, he was quite intelligent, etc. Think of President Roosevelt. Handicapped, overcame odds, had a strong woman behind him. It just depends who you think of. Each leader has their ups and downs, faults, weaknesses, etc. The best leaders know how to overcome the bumps and grinds in their way.