It’s hard to really know people, and that fact, I think, applies as much to oneself as to others. It’s hard to know who you are, and it’s sensible and not narcissistic to occasionally inquire into the nature of one’s self.
The means of mirror gazing are many. For artists the self-portrait is one means.
Naturally just as one witnesses different aspects of other people, just in that way it shouldn’t come as too much of a surprise to discover that one finds different facets to oneself.
And you can portray yourself in different ways. And why not deliberately seek to know these other aspects of the self? Or if one only stumbles upon them, that too is knowledge….