Although the face peering back at us in the morning as we brush our teeth is the one with which we are most accustomed and at ease, it is not the true reflection of who we are. As a reflection, it depicts how we appear when facing the other way. Seeing how we appear in photos might be startling because we’re so accustomed to seeing the reverse image of ourselves. And the image of you in a photo can be much more awry unless you have a naturally symmetrical face.
We see ourselves in the mirror all the time—you wash your teeth, you shave, you put on cosmetics.The act of looking in the mirror leaves a lasting impression. That familiarity is yours. Recognizing something breeds liking.
This phenomenon is known as the “mere-exposure” effect. In essence, it’s a psychological theory put forth by Robert Zajonc that asserts that people respond favorably to things they are most familiar with. Therefore, because it’s the opposite of what you’re used to, you immediately despise or even find it grotesque when you encounter a reversed version of yourself.
In other words, even while it’s true that we appear better in images, we’re more likely to feel that way psychologically when we gaze in a mirror because a mirror shows the reverse version of someone and hence just a reflection but not the true self.