sometimes, psychology (wishful thinking, denial, cognitive bias, blind spots, ideology, ...) is stronger than intelligence.
alan greenspan's comments on the financial/economic crisis:
I found a flaw in the model that I perceived is the critical functioning structure that defines how the world works, so to speak.
That's precisely the reason I was shocked because I was going for forty years or more with very considerable evidence that it was working exceptionally well.
those of us who have looked to the self-interest of lending institutions to protect shareholders equity, myself especially, are in a state of shocked disbelief.