What concept do you see negatively that most people hold as a virtue?

Consistency.

There are lots of quotes on why consistency is overrated, which I won’t verify because I’m on my phone. Keynes’ “When things change, I change my mind; what do you do?” Emerson’s (?) “Hobgoblin of small minds”. Whitman’s “I contain multitudes.”

But the world has ever admired, and the world has long been led, by adamant, unyielding, assured men of conviction.

Usually led right off a cliff.