Perot Museum: Mistake or Science Lesson?

I visited the Perot Museum of Nature and Science in Dallas with my family this week. Among the fantastic interpretive signage and exciting interactive exhibits, I naturally found time to snap some architecture pics. I thought the smooth, individually sculpted precast panels were masterful, and the prism expressing the escalators whimsical. It was precisely because I was admiring the precast that I started looking at other concrete work and noticed a problem - or was it one more science lesson?