But large companies tend to have MBA types scurrying around rooting this stuff out as it pops up or shortly thereafter. Government has no such sort of immune system to fix these problems on the go. It just gets sicker and sicker until the tax payers vote for something drastic or revolt.

You see this in nonprofit entities too. They get big, abstract away from their mission and waste a lot of money until someone gets tasked with cleaning house or a more mission-driven comes along and replaces them.