Your face isn’t perfectly symmetrical, so when you see it in a picture vs a mirror it looks off.
There’s also some kind of psychology with mirrors on top of (including?) the symmetry thing. You see your reflection every day in the same mirror, in the same lighting, from the same angle and distance, and you grow used to it so you think you look really really good. And you do! But then it’s jarring to see yourself differently.
Your face isn’t perfectly symmetrical, so when you see it in a picture vs a mirror it looks off.
There’s also some kind of psychology with mirrors on top of (including?) the symmetry thing. You see your reflection every day in the same mirror, in the same lighting, from the same angle and distance, and you grow used to it so you think you look really really good. And you do! But then it’s jarring to see yourself differently.