Or has yet to find a suitable successor.
he was in office for 24 years after another full career. He had time to find a woman, have several children with each of them, raise all one of them to adulthood to his own exacting standards and discipline and hold a deathmatch competition amongst them to determine a worthy successor from his own bloodline.
In his long career, he had a staff. A cadre of supposedly qualified people who supported his efforts. Undoubtably, some of those staff were long time assistants and confidantes. Never, in the waning years of his 24 year career, did he look at even one of them and say, you know this one has it. Once I hang it up, he'll be a worthy person to sit in my chair.
It's absolute hogwash that he couldn't find a worthy successor in 24 years.