Disclaimer: I am not a mentor, but this rant is coming from my friends' experiences as mentors.

Now, Mentors are supposed to help right? Group with the lower level, perhaps new players and help ease things along?

Now. Mentors' goals is to help and give advice, say, in the Mentors' Roulette.
But whenever you try that, people tell you to shut the fuck up, or even just outright kick you, claiming 'Don't tell me how to play my Job.'
And when you're absolutely silent in runs, the low-level players cry 'Why didn't you help us or give us advice? You're a mentor, that's your job!'

Not joking when I say this happened almost every time they got in groups.

I'm sorry, but.. My god. What the heck do you expect them to do? You yell at them for doing their job, and then when they don't, you scold them anyway.

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I really hope not all people are like this X_X I was finally considering trying to become a mentor, but after having heard these things from my buddies, I'm terrified @.@