In Western culture, some things that appeared normal did not necessarily seem normal elsewhere in the world—for example, corsets.
Once older women reached a certain age, they would teach girls to pay attention to their appearance. Even if a ballet dancer already had a good figure, her teacher might say that if she could be a little thinner, perhaps she would dance better.
Mothers and older women were often the "messengers" who conveyed society's messages and values. They told girls what men liked. Boys faced the same problem—for instance, when elders went fishing, they would tell them what kind of man represented success.
Many people's sense of self depended heavily on the praise of others. To gain society's approval and ensure that they got along with others, even people they disliked, they put on a personality mask, even if that mask was vastly different from their true character.
The more praise that personality mask received, the more they treated it as their true personality, until they could no longer recognize themselves. Even when they discovered that their real selves differed greatly from the mask they imagined, they refused to acknowledge their true personality flaws.
In psychiatry, this was called a personality disorder. It was prone to arise among certain groups of people with long-term, rigid thoughts and behaviors. Its proportion in America's published psychiatric prevalence surveys was not high, but the impact caused by these people was great. They usually made themselves suffer and made others suffer as well, yet all they wanted was praise.
In other words, for these people, becoming what others wanted them to be was easy; becoming themselves was difficult. He practiced the piano with great impatience. What he really wanted was to play baseball, but winning awards for piano would make his parents proud. Parents