The title comes from one of Gilbreth's favorite jokes, which played out in the film, that when he and his family were out driving and stopped at a red light, a pedestrian would ask: "Hey, mister!

Gilbreth would pretend to ponder the question carefully, and then, just as the light turned green, would say: "Well, they come cheaper by the dozen, you know", and drive off.

Frank takes every opportunity to study motion and increase efficiency, including filming his children's tonsillectomies to see if there are ways to streamline the operation.

The voice-over at the end of the film informs the audience that Lillian went on to become the world's leading efficiency expert and Woman of the Year in 1948, a title bestowed by the Twentieth Century Club of Buffalo.

[9] John McCarten of The New Yorker was less enthused, writing that "since nothing much happens in the way of conflict, there just isn't any drama, and the piece boils down to one of those typical fluffy comedies about home life in America.