[betteringred]

> What am I missing?

Context. If I'm in a bright room (office), and the last page I visited was black on white (the default/norm on the web), and the page I view after this one will be black on white (most likely), then viewing this one in the middle in white on black is jarring, annoying, inconvenient, distracting, hard to read (because my eyes have to adjust) etc.

If one is in a dark room, and has a custom stylesheet to display all pages in white on black, or if the web were predominantly white on black, then sure it's OK.