It's important to keep auditioning. If you're auditioning for something, you're auditioning for a role that people can't see you in and you need to convince them that you're the right person.
One of the things that I was interested in about Moriarty was - he's so manipulative that he doesn't need to commit violence himself or kill people - he can get everyone to do what he needs to do. And sometimes they don't even know that they are being manipulated by him.