I'd note that the system isn't anywhere near as corrupt as the quest present circumstances would suggest. Normally all this is backed up by Imperial audits and Inspections(hence the title), a negligent or incompetent official could expect to be punished, stripped of their titles and often exiled(execution).
You'd appoint people first by loyalty, then by reputation, then by competency. It tended to work out, its hard to be good at it, but its also hard to be terrible at it.
The big problem was broad loss of trust in the system, because when you have subordinates paying you to work for you, then theres vanishingly little incentive to actually act upon their misbehaviours.
Secondly, when people buy a title, they expect to get their money's worth, so instead of administrators taking care of the land for pay and prestige, the intent of the system is subverted, they paid a hell of a lot for the title, so they're going to get their money's worth in extractive methods, since the titles weren't inherently heritable, you're better off looting the seat for all its worth and adding it to your personal estates.
All told, the system could work fine, assuming title holders were proper Confucian men of virtue.
Thats a big assumption.
