The Power of Advertising
The majority of beauty adverts from the 1920s are illustrations. Even famous faces were most likely drawn. Photography was used occasionally.
Some adverts have a lot of narrative, describing in great detail how wonderful their products are and how to use them. As a result, we get a real insight into the thinking of the era.
The way women were depicted in adverts changes throughout the decade, from shy and demure at the start, to confident and sexy by the end. In the same way, this was how the wearing of makeup progressed through the decade. That is, at the start of the decade, makeup use was a little on the cautious side. By the end of the decade, not only was wearing makeup fashionable and respectable, it was de rigeur.
The growth of cosmetics during the 1920s was rapid and dramatic. The number of brands and products increased tremendously.