I think the script is the key. Regardless of how great everybody else is working on a film, if you're working on a script that you don't think is great, you're not gonna be able to make a great film. Whereas if the script is great, then you can.
Then, one day, when you least expect it, the great adventure finds you.
I'm sure it's not great fun for them, or for any parent, when their child says they want to be an actor, 'cos it's quite an uncertain business and it can be terribly hard for most actors.