History lesson (huge oversimplification): The Roman republic (which eventually evolved into the legendary Roman Empire) really didn't want any one person with too much power. So, instead of one single leader, they had two, called consuls. These consuls also could only serve for one year at a time.

They knew this, so they basically tried to get as much glory and honor as possible in only one year. And since the best way to gain glory and honor was military victories, Rome often would aggressively attack and conquer territory.

Because the consuls could only rule for a limited amount of time, they became very dangerous. The same principle applies here.