The Yongle Usurpation
The Ming founder passed the throne to a grandson, skipping his surviving sons. His fourth son, holding the northern frontier armies, rebelled and took the capital in three years; the young emperor vanished in a palace fire and his body was never identified. The usurper, ruling as Yongle, executed his predecessor's officials and their families in the thousands — one scholar who refused to write the accession proclamation had ten degrees of his relations killed — then moved the capital to Beijing, built the Forbidden City, and sent out the treasure fleets. The rumour that the deposed emperor had escaped is one suggested reason those fleets went looking so hard.
The orderly transfer of power fails because no rule or claimant is accepted as legitimate.