I like symmetry. I regularly try to arrange things so they are either perfectly symmetric, or not symmetric at all. It's almost obsessive.
What is the reason for this? I wish I could say for sure. I have no real way of knowing, only hypothesis.
The most logical explanation I have thought of is that this is an evolution-related function. When babies are first conceived, the zygote's external appearance is perfectly symmetrical. If the zygote continues to grow symmetrically, it indicates 'better' genetic material. People with this 'better' genetic material would produce offspring less vulnerable to inherited disease, and thus more likely to survive to produce more offspring. Resultantly, symmetrical girls/women are attaractive to me, and with them, everything.
This is a rather the selfish gene-esque explanation, but it seems comfotingly logical to me. Your comments are welcomed!