Explanation: Roman Emperors, both by the nature of men in power and the needs of the job, generally made a lot of fucking enemies, both contemporary and in the recollections of history.
Antoninus Pius is a rare exception, a man who came to power by uncontroversial means (being chosen as a successor by Emperor Hadrian for his integrity), ruling through a period of uninterrupted peace, prosperity, and legal reform, having few vices and living a simple and unextravagant life, and then handing power over to a well-regarded emperor (Marcus Aurelius, and, less importantly, his adoptive brother Lucius Verus). By the recollections of those who lived after his rule, his mildness and attention towards public good and infrastructure was highly regarded, and in his personal life, Pius was likewise uncontroversial, and his adoptive sons and their tutor remembered him as a kind man who enjoyed the simple pleasures - fishing, comedy, theatre, watching boxing matches.
We love Emperor Pius in this house!
So you only get up to one benevolent and capable leader per empire it seems …
One might also count Titus, as his Emperorship was universally beloved as well, but he made a lot of enemies before becoming Emperor (including a stint as a conquering general, and then his father’s head of secret police 😬), while Antoninus Pius rose to the position without stepping on any major toes.
Not the only one to retire and go mad stabbing stray fishermen on his island style resort on the taxpayers coin Antoninus Pius?
Nah, the one who went to an island resort and tormented a stray fisherman (supposedly) was Tiberius. The only one to actually retire, permanently (as Tiberius eventually, reluctantly, returned to Rome) was Diocletian, who died farming cabbages somewhere in the Balkans.
Antoninus Pius died much as he lived - quietly. Got a fever after a dinner at his estate, knew his time was coming, passed imperial affairs to his adoptive sons, gave the bodyguard the password for the night, and died.
Ah, Many Thanks PJ,