Its just the lighting. My hair looks great in the mirror on one side of the bathroom, where the light only comes from above, and it looks so frizzy in the other mirror in the same room, because the light comes from the back. The back lighting really shows off the frizz.
This reminds me of a Seinfeld episode, where the booth in the diner has such bad lighting it makes the prettiest girl look ugly.
I used to read the Mineral Makeup boards. One gal was so convinced that her skin had a greenish cast, she kept ordering samples of mineral powder to match it. It became a huge drama between her and the woman who sold the powder. Finally, after months of crazy posting, she realized that the color was due to her bathroom lighting.