Page "Yangban" Paragraph 11

Sadly, the fact that there were at most only 100 positions open with thousands of candidates taking the exams, competition which was originally supposed to bring out the best in each candidate gave way to the importance of familial relationships.

Luckily because the Joseon Court was constantly divided between the Northern, Southern, Eastern, and Western faction members ,-- the eccentric geographical naming derived from the location of each leader's house in Seoul — which they themselves were divided into subsections, resulted in a weird divided system of where corruption was very difficult.

With each faction constantly probing for an excuse to kill off the other faction, if one faction was proven to be corrupt then the other factions would immediately jump on the chance to purge them.

The attempt to receive or give bribes on a massive scale was suicide.

It wasn't until the reign of King Sunjo that the Kim clan of Andong in cooperation with few other blood related clans finally obtained full control over the court after purging not only their rival factions but other rival clans within their own political faction that the Joseon bureaucracy degenerated into corruption.