Excitement! Followed by disappointment and disillusionment.
That's what I experience when I hear someone claim to be an anarchist, but then they start advocating communism.
Or when someone expresses an interest in science but then begins talking "flat Earth" or demanding I devote my life to "Climate change".
There's the promise that a person is sensible and someone I can relate to... and then they expose their "but".
How often does that happen to you?
And what issues do you experience this with?