In the past it was unheard-of for men to paint their nails: it was considered a female habit as it was aimed at making any woman look neat and beautiful. These adjectives were not to be associated with men, who were supposed to be macho, masculine and natural.
Things have changed in the twentieth-first century. Society is gradually evolving to a more liberal and accepting environment where everyone is free to do whatever brings them happiness. And a pop of color is the best way to bring some liveliness in your mood that can lead to fun adventures. So, both men and women can proudly wear a nail polish pendant in order to showcase that there is no gender stereotype that can stop them from living their best lives.