Personally, I wasn't getting frustrated when I started playing c-rpg, because I realized I was a noob and people around were pros.
It was more like...
"Oh, this guys wears a nice looking hood and he's a crossbowman, that's amazing!",
"What a knight over there, he looks so shiny and cool",
"Oh my god, this dude is amazing at killing those guys",
"I'm being fighting in such a big battle, there are so many players around, that's great!".
The frustration came a bit later, but at that time I was already highly addicted so I didn't quit anyway.