It's no wonder actors feel bewildered, hurt, or angry when they're not cast. I did too, sometimes, when acting was what I did. It's one of the reasons I like directing -- I don't have to be cast as the director, I just have to show up.
Often the more enterprising auditioners will ask me what they can do to improve their auditions, to make it more likely they'll be cast in the future -- and I have nothing to tell them. Actors have no control over the casting process, none at all, and there's *nothing* they can do or say or be that's going to get them the job every time (or even most of the time). Well, except doing some prep work like reading the show ahead of time, or maybe learning how to act, stuff like that. But even then it's a crap shoot.
See, there's no universal standard for what makes a good actor. The things I like about an actor may be exactly the things another director despises. I cast my friend Mike in a lot of my early shows with Civic because I saw a certain interesting quality in his work -- to me, he seemed like an Everyman type, but with a twist. He's the sort of guy you look at on stage and immediately identify with, even before he opens his mouth. The twist is, he's a really smart actor, and he can't hide that. Even when he's playing a dumb character, it's a dumb character with a certain amount of native cunning -- the brain just doesn't stop working with Mike.
So I liked that about him, and I didn't understand why he wasn't being cast in almost every play Civic put on. Turns out other directors didn't see him the way I saw him, at least not until I'd put him in a few parts and they'd had a chance to see how versatile he was. They saw a guy who was reserved, quiet, maybe even bookish -- and who wants to look at that on stage?
So yay me, I cast him a lot and other people saw him and realized he was good. Of course, now I can't get him to audition for me any more because he's too damn busy doing other people's plays!
The point is, I saw something in him that other people didn't. And other directors see things in actors that I don't, and it's not until much later that I realize, oh yeah, that *was* the perfect actor for your play -- how'd you know that?
Actors shouldn't tie themselves up in knots over being cast, or over not being cast, at all. If you're cast, pat yourself on the back and know you got the part because of your amazing talent, beauty, and charismatic personality. If you're not cast, know that you lost the part because the idiot director wouldn't know good acting if it fell out of a tree and bit him, and besides, it's obvious he has the hots for the person who *did* get the part and you sure feel sorry for both of them, but really, they deserve each other because they're so shallow and not very attractive, either.
Then go audition for the next play.