Being new to a dungeon doesn't mean you are automatically a clueless player. I've seen "new-to-dungeon" people come into a party and know exactly how to perform their job correctly, which entirely makes up for their lack of experience in the dungeon as they will pick up and adapt to the environment with only a little prompting on less-obvious things from the group.

People have to stop judging books by covers, and also learn to be more involved with the community by assisting other players -- this makes for a better community overall.