If a person's first post is spam, trolling, racist or pornographic then (my guess) is they get permabanned because they've made it clear that they have no intention of contributing to the community.
I think in general it depends on how you present yourself and if you're liked before breaking the rules is concerned. For example someone (Put_lead_in_gates_head) was banned because he chose the wrong name, people prejudge him and he was labeled a troll before they even new him, he was eventually unbanned and has become a well respected mod. kintaro has got away with more because people like him and make allowances because they know he has problems, I think he's a nice bloke too (the only thing I think he is ever guilty of is attention seeking).
MrX was banned even though he (technically) broke less rules, he was banned for being an immature idiot who no one liked. I actually miss him I think this forum really needs a troll (just as long as they're labeled as such) we need someone to be the butt of all jokes and to mock when there's nothing else better to talk about. I say bring back MrX be nice to him (if he wants to become a good member give him a fair chance) then if/when he acts an arse label him a troll, even better make his troll status invisible to him and guests but not to other members - go on Refalm it'd be fun.
Who do you think were the worst/best trolls?
I would vote for the following, (first the worst) (in my oppinion):
slave 1,135 posts and no ban but troll status awarded.
Solaris 598 posts and still no ban or troll status!
MrX 401 posts before a ban and multiple accounts to.
Great_Satan 340 posts multiple accounts before banned.
I don't know who's worse MrX or Great_Satan, at first I thought MrX because he was less blatant and he got away with it for longer but Great_Satan was more offensive, however ripping the piss out of MrX was fun so I don't know.