The problem with the mentor system is too many people either expect too much out of it or don't actually understand what it's actually for.

As for mentoring itself.

If someone is actually asking for input I have no problems providing it. I rarely provide it unsolicited in game simply because there are too many lazy bad players that have no desire to get better and I choose not to waste my time trying to help people that refuse to help themselves or have any desire to improve. If you don't give a damn about yourself they why should anyone else? And a number of those people are mouthy little brats that think they know everything when it's plainly obvious to anyone with functioning eyes they're completely clueless...