This review contains spoiler.

Kyungjin is right. Wouldn't it be good to work with a rich and powerful person? Yisoo can give Ganghyun's team the resources she needs, including intel and insider information. I think Ganghyun knows that too, but she doesn't like the idea of working with a chaebol kid. Either she's prideful or a rich person was involved in her father's dismissal.