War posters that are symbolic do not attract a great deal of attention, and they fail to arouse enthusiasm. Often, they are misunderstood by those who see them.
How to Make Posters That Will Help Win The War
Office of Facts and Figures, 1942

The Government tried to identify the most effective poster style. One government-commissioned study concluded that the best posters were those that made a direct , emotional appeal and presented realistic pictures in photographic detail. The study found that symbolic or humorous posters attracted less attention, made a less favorable impression, and did not inspire enthusiasm. Nevertheless, many symbolic and humorous posters were judged to be outstanding in national poster competitions during the war.