The biggest reason is obviously because of their fans. What I like about new groups are they are free from this 'my bias is a victim' drama. So it's really enjoyable to stan them and involved closely with the fandom on internet. It's fun and the fanbase are more unite with less dramas like this. It will happen too in the future but at least for me I can enjoy it while it last. However, with ex popular member from survival shows as the member, the dynamic of the group change a lot. Fans keep complaining their faves get less and their faves should be appreciated more because they're more popular than the other members. It's super annoying.
I mention hybe because I understand that groups from medium to small companies, they need a push to make their group popular. Like Ive with Wonyoung and Yujin, but obviously for company as big as Hybe, they didn't need it. I don't think they will poach other survival shows trainees anymore which is good.