Those at the very top of the power chain tend to lack important characteristics such as empathy, compassion and genuine care. They're cut-throat personalities, driven by a materialistic nature which see's their dark side rule first and foremost. Power, lust and greed are the only actual emotions they possess.
This is why we see so many sewer rats given positions of power, but my question is- Does power always equate to corruption, and if so, why ?