There have been few studies about what causes people to become bureaucrats. Is becoming a bureaucrat an inherited trait? Is it learned behavior? If we google “personality traits of bureaucrats”, there is some literature on the subject. Googling “life of tree frogs” shows about as much academic effort in that field.
No one seems to want to study bureaucrats. No tax-funded academic would dare to do so, or be allowed to do so, without first guaranteeing the validation of some pre-conceived notion that their importance and abilities put them in a class of people worthy of favored treatment. Similarly, no academic who might someday seek tax funding would want to alienate his future source of income.
So, most of us are left to define bureaucrats on our own. It’s an enjoyable pastime.