Girls with good/bad - attitude

Probably not the right title for this but on the odd occasion I've watched any shows I've found it very easy to spot the girls who love their role and those who aren't too fussed. Beth for example puts on amazing shows, interacts with viewers and generally makes it a fun environment. Tegan on the other hand often seems like she can't be bothered.

It got me thinking, how much lies within the ego?

Do all of the presenters feel they are naturally good looking so know the glamour/sex industry would work for them? Or it is something else.

There must be a degree of confidence to go on screen and get naked and in some cases talk about fantasies you may have never even played out in real life to people you don't know.

So my question to you guys is. Do babes enter this industry knowing they are good looking, knowing they are hot? Or is there something else that leads to the performances we see