I'll try giving you an answer that doesn't boil down to "It's a PvP server HuRrDUrr":
It's an old, well organised server with all the boredom that comes with it - factions are skewed in regards to their PvP affinty, a lot of battlegrounds are won before they're played if you know the names of the pvp scene and who you're up against.
It's a lot of hit and miss and I'd rather not get into the specifics of WHY that is - more eloquent people than me have tried to have this discussion, it usually gets dismissed. I'm just tired by now.
In short: It's all so damn predictable and boring at this point.
That's where you come in. If I gank you for half an hour, who knows what will happen?
Maybe you will log over and flame. Maybe you have friends to fight me, so I can get friends and so on - emergent gameplay, if you're familiar with the term.
Until one side brings a whole raid, which they absolutely will if you're in a pvp guild, some multiboxer destroys said emergent gameplay, or you log out frustrated, everything about this is more fun than ANOTHER RBG, no matter if WSG, a farm-AV or Wintergrasp.
TL;DR: PvP on Warmane is stale, has been for years now, and ganking you promises more entertainment, whichever way it goes, than playing duel N°5348 or another BG.
kind regards,
Trommel/Bernd
see you when you gank me back!