im pretty sure its just that if you spam/do something against the rules you get a tempy, and if you continuously spam/do something REALLY bad its a permanent.
If someone repeatedly spams, say's innappropriate language, hacks, ect, the are banned for a small period of time. Now, if they are allowed back in, and keep hacking, spamming, and cussing, they are banned permanately.
The mods are the only ones allowed to ban, obviously.
If some one spam's you click the flag and I have banned 4 people from this site, ____________________________________________________________ (Example Of Spam) shuefieofwfhueruhgehuhuerhgherghue,..,.,.,herhaejahseko ____________________________________________________________ If they do that over again and again they will be banned.
Flappyboy summed it up really well -- honestly, anything that goes against the Terms of Service/Conditions will result in a warning, which will eventually lead to a temporary ban then a permanent ban. Imagine it as three strikes. If the moderators/admins feel that the user did a certain act that violates the ToS/C in excess, they can just as easily ban them permanently
If you want to know why he was banned, you should contact Carlie. I'm pretty sure I know why since I was around but I won't discuss it.
Whether you get banned or not, as with every site I've been on, is arbitrarily dependent on the seriousness of the offense and whether or not you should know better (previously warned or an older member of the site).
Definitely forward those questions to a moderator or Carlie. I doubt many users would know the correct answer. Unless of course, you've been temporarily banned before. Also, like Gantic wrote:
Whether you get banned or not ... is arbitrarily dependent on the seriousness of the offense and whether or not you should know better
So, the length of a temporary ban may depend on how serious the offense was. It's hard to know, so my best advice is to ask a moderator/Carlie