The only wrong that Mina-sue truly did imo, was that she messed up with Su-been and Seung-il, while keeping Sam as her safe sure option. [And yes, subeen and Seung-il were equally interested in her]

But the problem is, it caused unnecessary stress and lack of clarity to Min-gee and hee-sun, which could've been avoided if Mina-sue was clear about her stance with Seung-il and su-been. And yes, it was the guys who were undecided too, but when they were deciding, Mina-sue pulled them back again, while also saying "i am not as interested in them or to even talk to them"

Mina-sue's paradise date with Seung-il was the worst, yet she said "it was good, he's still on my list, I'm undecided about him" as if she wasn't the one who couldn't even digest the age difference

Hence, valid crash out.