I have a quick test I use when judging a protagonist: could I imagine sharing a cramped bus ride with them for an hour without wanting to escape? If the answer is no, the character might be priggish. That quality — moral self-superiority, constant correction of others, a tone of 'I’m right and you’re wrong' — creates a barrier between reader and story. Readers need pockets of vulnerability or contradiction to latch onto; otherwise the character reads like a pamphlet.
From a craft perspective, priggish characters can also
sabotage theme and conflict. Fiction thrives on tension and uncertainty. A protagonist who never doubts themselves or scoffs at others’ perspectives reduces dramatic possibilities. Even if the story is meant to critique that behavior, it’s a tricky tightrope: if the narrative isn’t obvious enough about its irony, readers may simply feel
lectured. I’m thinking of books where authorial voice bleeds into character voice — that blurring often makes moralizing feel like an editorial, not a lived human experience.
On the flip side, a priggish protagonist can be compelling when used intentionally: as a vehicle for redemption, satire, or to expose social hypocrisies. But the key is balance — give them scenes that reveal doubt, incompetence, or growth. Otherwise I’ll start noticing the seams and lose faith in the whole fabric of the story.