It’s the uncanny valley effect, isn’t it? Like, almost everything in Rockwell’s paintings is photorealistic but the facial expressions are slightly too caricatural, too exaggerated too be real. Human faces don’t quite work the way he paints them. On one hand, those faces convey an emotion instantly On the other hand, it’s an inauthentic emotion, theatrical, even dumbed-down - all ambiguity removed and subtlety forgotten. The girl is Proud, the woman is Concerned, the principal is Reflecting.