Insults vs Sarcastic banter

I'm a bit confused. (as usual) I review the forum guidelines once in a while but still miffed.
What are the top reasons members get banned? Still cannot figure it out. When I see a member banned do I assume a he went for the juggler of another member and it was pulled down by the mod before it was viewed? I go back through their last couple posted to see if I can figure out what got them banned.
Or is it too many minor violations, like posts which should be private, exposing a member or provider identity?
And once banned...what is your penalty? no DM of members? How do you get unbanned?
No one needs to answer all of this but a few thoughts would help.

Each infraction of guidelines involves the member getting awarded points. The points given differs in value . From 2 pts up to 10 pts per infraction. Some infractions carries automatic ban.
If you accumulate 25 points you get banned for 90 days. Some bans can be longer. Most members get banned from accumulating the 25 points.
Most of those infractions are from insulting remarks or the heinous thread hijacking infraction
There are some other variables at play as well. Hope this helps

Outting a member carries auto ban usually for one year

Thanks Winn. I just found my infractions tab. Had a few. Some expire and have 5 points now. Will read through my past sins. Have a better feel now.