The director’s job is NOT to get you, the actor, to give a better performance.
That doesn’t mean that directors will not help you turn in a better performance. Hopefully, every director you work with will contribute something that improves the final product, whether it be a rehearsal environment that is conducive to your best work, a well-timed question about your character, or a creative idea that you wouldn’t have thought of yourself. All I’m saying is that it isn’t their job to do that. And even if it were, most of them can’t.
Many years ago, when I was young and loaded with lots of natural talent and good instincts but little technical prowess, I did a professional production that had a scene in which I apparently stunk. So badly that I was essentially “kept after school for extra help.” The director, who was also a very fine actor, did his best with me. We spent an hour together, with him trying to explain what he was looking for or what I was supposed to do that was going to fix this dreadful scene.
I had no idea what he was talking about, and I could see him getting more and more frustrated with my inability to give him what he wanted. I felt terrible about my obvious inadequacy, even if I had no idea in what way I was inadequate, but had no ability to express my confusion or to interpret anything that he said in a meaningful way.
I think he eventually just accepted that I wasn’t going to be able to do it well, as I don’t remember a lot of additional work on the scene after that.
A director like me (a good, articulate actor who is also a teacher by nature) can help you deliver a better performance than you can get to on your own. As one of my actors said, “You really teach when you direct, don’t you?” (Although most of what I teach in rehearsals can’t be retained long-term, due to volume.)
But really, I’m the exception to the rule. If an excellent director and actor like Lee couldn’t do anything about my sad portrayal, despite the oodles of talent that had gotten me the job in the first place, then most directors without his understanding of acting aren’t going to be able to help you, either.
So don’t expect them to work miracles. You are the only “saint” you can depend upon for this. That means putting in the time, both in rehearsals and out.