Mentors are supposed to try n smooth out the rough content new players attempt doing when they que for EX/Savage content.

Instead of trying to explain that this is generally cleared in the party finder groups or giving it a shot anyway after trying to explain the mechanics mentors either leave or the people who qued are toxic towards the person trying to say "hey this fights mechanics are super complex so if u guys wanna try here's how it works."

In reality it's a flaw on both sides of the spectrum and really the requirements are insanely low. Idk how it works on JP data centers but I imagine it's slightly better than English ones.