James Madison understood that all forms of government had a fundamental flaw - they are run by human beings.
If men were angels, no government would be necessary. If angels were to govern men, neither external nor internal controls on government would be necessary. In framing a government which is to be administered by men over men, the great difficulty lies in this: you must first enable the government to control the governed; and in the next place oblige it to control itself.Monarchies are dictatorships with no inherent form of self control (checks and balances). Monarchies come in all shapes and sizes, not just the long line of Kings of England or other dictatorships that come to most people's minds. They exist in our city governments, state governments and federal government agencies as well.
Your local department of building permits is often its own little fiefdom whose primary goal is self preservation. During good economic times high tax revenues allow budgets to expand. The assistant to the head of the permitting department suddenly finds themselves with their own new assistant. But when the economy falls the new assistant to the assistant is not let go, services to the public are trimmed instead. The bureaucracy is not trimmed, services are trimmed.
Chose any governmental department you wish to examine and you'll see this is true. Your local school district, for example, will have twice the number of workers in "administration" than they did 20 years ago. The number of teachers on the front lines may have only fluctuated slightly, but they miraculously have twice the number of bosses than the predecessors of a generation ago. As an example, this chart shows the number of managers vs faculty in the California University system.

As these Monarchies and Fiefdoms grow they become less and less concerned with serving the public. The original purpose of the bureaucracy is buried beneath their goal of self preservation - retaining benefits, staffing, and budgets. Look at most any municipality you wish in the United States faced with budget cuts during down economic times. The first thing they cut is fire department and police budgets. The most basic of services, those designed to protect the citizens, are the first on the chopping block.
Talk about fuzzy on the concept - these bureaucrats have lost all focus of why they exist in the first place. To protect the citizens.
When these Fiefdoms grow large and unwieldy the citizens get fed up and demand better government. In response, bureaucrats promise to launch an investigation, maybe hire a few more consultants, and promise to get back to you. They investigate themselves. A year later when the results of the investigation are announced, low and behold they have discovered a few areas where they promise to do better, which of course will require a few extra bucks.
Reports never come back and announce, "Oh my God, we have become a Godzilla rumbling down Main Street destroying everything in our path."
There are no mechanisms in place obliging government agencies to control themselves.