You can't do opera when already from the 10th row you can only see little dolls on the stage. In such an enormous space you can't put much faith in the personal presence of the individual singer, which is reflected in facial expressions, among other things.
When you go out onto the stage, all the preparation has to be forced into your subconscious. For the moment of the performance, we all have to return to a new level of unconsciousness. All the reflection and all the doubts have to be laid aside before you start.