The reason why I.O.I is coming back is because the girls are flopping in their main groups. Yeonjung, Somi and Chung Ha obviously don't need this, not quite sure why Chung Ha agreed to it, I guess she loves the girls a bit too much. PRISTIN gone, gugudan good as gone, Chaeyeon and the backup, sorry, DIA, good as gone, Sohye could use some attention, Weki Meki is literally nowhere.
I.O.I is coming back at least for those girls to maintain relevance. Sorry galz, you ain't NU'EST, girl group market is too saturated, you need a bit more to stand out.