Yang Hyun Suk broke his own rule of not accepting trainees from other audition shows.
He had given himself the rule when starting his audition show 'Mix Nine'. One of the labels he visited was FAVE Entertainment, which had trainees such as Lee Soo Min, Son Ye Rim, and Park So Yeon. All three girls are from audition shows - Lee Soo Min was on 'Produce 101' and 'K-Pop Star 6', Son Ye Rim was on 'Superstar K3', and Park So Yeon was on 'Produce 101' and 'K-Pop Star 2'.
Following his own rule, he rejected all three of them - however, he decided afterward to choose more trainees, and one of the trainees he chose was Lee Soo Min because she was so talented in her audition. He kept his decision not to accept Son Ye Rim and Park So Yeon.
You can check out her "Wrecking Ball" below.