Apink was once the trend girl group back when they debuted. There were the 'it' group with their refreshing "cute" and "innocent" concepts back in 2011-2014.
However, after five years of being in the music industry, Apink has been declining in terms of the number of fans and somehow their digital sales are also failing. With the entire new trendy girl group like Gfriend, Twice and Blackpink, girl groups that debuted back in 2011 are being replaced.
Pink Pandas are now demanding Plan A Entertainment, Apink's agency, to manage the girl group better. Apink has definitely the fandom to back whatever they release but the public is not as interested to them like they used to.
Many Korean fans are thinking that it is because Apink has been doing tours outside the country that some of their Korean fans are hoping onto fresher and newer girl groups. Many fans are hoping that Apink would change their concept or release a better song.
Some people are getting tired of their "same innocent" concepts. Many fans, especially international ones, want them to try and do sexy concept. They all know that Apink members can pull it off because of their special performance on their concerts.
Apink members have established themselves. Eunji has established herself as the first "Reply" actress who proved that idols can also act. She has also proven herself as a solo singer. Another member, Na Eun, has proved herself to be one of the "it" girl group idols. Bomi has launched herself as one of the best female idol in variety.
Fans are thinking that if Wonder Girls can completely reboot their style and concept for the better, maybe Apink could too.
I also think that Apink can completely do it as long as their company will give them the right songs and the right timing.