ON ACTING: Surprise!
For example, watching themselves in a re-play of love story, the actor might respond: "My God, look at that. My deep involvement in a love relationship has elements of sadness in it; and sexual need. Oh my God, look at my confusion! I’ll be damned.”
They review their performance as an outsider: “So that’s what I'm like when I am under that kind of dramatic pressure".
That reaction indicates that the everyday subjective personal view of the actor has been replaced by a more insightful after-the-fact objective side of him/herself; and properly banished are the dreams, hopes, desires and often denials of the would-be actor, to be replaced by the brutally honest (and perhaps cheering) evaluation of the actor as objectively viewing audience.
Hooray when that happens: it means that the actor had been earlier performing on set not as actor/director (watching themselves during performance), but had been living during the actual performance at a surprising level of depth, profundity and complexity that even the actor herself had no idea what she was emotionally capable of achieving.
A happy surprise!