Hey /fa/

What's the SCIENTIFIC reason as to why people look really good on somedays, and terrible on other days? In conjunction, why do people look bad in the mornings but good at night? ( face wise) Also, why in the mornings when i wake up I seem to lose my jawline/facial structure/defined chin and my face looks like just like a boring face with no structure? This also happens when I come out of the shower (shower at NIGHT)