How can actors make the mistake of turning their back to audience?

There is no such mistake for actors to 'turn their back to audience'. Actors may turn their back on the audience intentionally, especially when they are trying to convey certain emotions or create a specific stage effect. For example, an actor may turn away from the audience to show vulnerability, shame, or anger. They may also turn their back to create suspense, mystery, or foreshadowing. Turning one's back on the audience is a deliberate artistic decision that can be effective in conveying meaning and creating a desired impact on the audience.