Selection of PvP team?

In a throw together group, how is your team determined?
I ask this because a few times I would look around my group and realize there wasn't a single monk in the group.

Sure there were warriors that chose monk as a secondary, but no primaries.
When I playing my monk I would often find myself as the solitary healer and that obviously would lead to my demise.

Was just curious about how groups are chosen...

Mind

just remember this coems from on weekend of BWE, but i choose to start with a necro/monk build, and hated it everytime a group would say hey we need a healer, oen it si my secondary so nto my main focuse for skillz, lvls, so i would have to use refund points to switch spells around adn had to by diff spells, about 200-300 gold worth plus my precious spell points to get these healing spells, so diffenitly a monk primary with jsut about any secondary would be nice but would like to see atleast two monk seconadaries ina group if no priamry adn atleast one secondary to back up the primary

I'm still looking for an answer about team selection...

It's just RANDOM, sometimes you're lucky with a monk, sometimes the opposits, depends on who's doing the 4v4/6v6...