"I am serious."
The cards were named after Shirley Page, Kodak studio model, human calibration tool, and possessor of skin whiter than fresh snow on an American Apparel store. As you might imagine, equipment tuned to make Shirley shine her brightest made those with darker skin appear "dulled and darkened," but no one much gave a shit up until the 1970s. That's when Kodak competitor Polaroid stepped in, not with a new type of printer, but with a new type of camera flash designed to better reflect black skin. We'd laud Polaroid's efforts ... if not for the fact that they only did it to better aid South Africa in enforcing apartheid.
In the end, it wasn't humanism, but consumerism that leveled the film development field. When producers of dark chocolate and dark-stained furniture complained that Kodak film made their products look shitty, Kodak finally took note. More modern Shirley cards feature not just a single, pearly white Shirley, but an entire mixed-race gaggle of them.