That one being the fact that he failed to see how he was being set up to take the fall for the fail.

Assuming, of course, he isn't complicit.

First, weaponized hypochondria was used to end his presidency a year before it formally ended. Fear of the "virus" used to shut down the economy that had been booming for the previous several years – so that Orange Man could no longer take credit for what no longer was. The same fear used to extend what had been Election Day to Election Months – during which time bagfulls of "absentee ballots" were collected and never vetted prior to being counted – by people who could be counted on to count them in just the right way. Orange Man complained about this after the counting – when it no longer mattered – because he no longer had any power to do a thing about it.

He did have the power, before the count. But failed to even try to exercise it – a failing the Left almost ever makes when it has its leprous hands on the levers of power.