Really, it isn't. It's solely your responsibility to keep yourself alive. Our job is to
give you an opportunity to stay alive! Our spells have a cooldown and can buy you time, so
MOVE! If you're getting pummeled, get out of there, move yourself out of the way. Go to a safer area, seek cover and recover that way we can conserve our revives and you can live to kill even more enemies. Please help yourself so we can do our jobs better.
This post isn't in no way directed at anyone specifically. It's more of a reaction to my observations on how some people attack standing still up front while they get hit and do nothing but wait for heals.
Cheers!