First, idol is a career that eats youth, and love is basically forbidden (even if it is not in public, it is basically established in secret). Women's love of beans is very fatal to popularity. Of course, there are some exceptions, but few of them can be ignored. Women who reach a certain age love beans and graduate.
Secondly, women in the Feiqiu family sell discs by shaking hands. Every song means many handshakes, which will take up a lot of trips and have an impact on their personal work. It is not a problem to ask for leave from the crew at both ends every three days. When individual work and combined work are unbalanced, they graduate.