Kpop fans (the general fans of the genre rather than people who are fan of selected few artists)
Kpop fans have this obsession with new and fresh faces. They want Idols to just roll out 4-5 after their debut and retire and open up space for new kids to roll in.
Frankly its kinda weird, considering that the rest of the world starts their career at early 20, while these people expect them to retire around that time!!!
No wonder so many idols, more so girl group members end up with anxiety disorders around that time when everyone tells them their life will be down hill from then on.