A phenomenon of Shichi-go-san (celebration for children of three, five and seven years of age) at the Seijin-shiki ceremony means the phoenomenon that, even though dressing gorgeously externally, young people participating in the ceremony were caught up in talking with friends whom they had not seen for a long time, did not show interest in the speeches or lectures by the head of the autonomy body holding the ceremony, and they became noisy during the ceremony, and as a result, the Seijin-shiki ceremony which was originally where they are to make up their minds as independent adults has turned into an opportunity to expose the moral degeneration of young people.
成人式での七五三現象とは、式に出席する若者が、外面的には着物で豪華に着飾っていても、会場では久し振りに会った友人との談笑などに熱中する余り、主催する自治体首長などの式辞・講演に関心を示さず式典が騒がしくなり、その結果、本来一人前の大人としての決意をすべき場である成人式が、かえって若者のモラル低下を露見させる場となってしまう現象のことを言う。