Maybe you like the default Window 7 desktop background.
It is pretty… For a day or two. After that, I’m ready for a change.
I like to entertain myself by putting puppy photos on my desktop, since I’m not allowed to have a real puppy. (My brother’s dog would object. I still wonder why she has any say in the matter.)
The ability to change the desktop background, window colors, sounds, icons, pointers, screen savers, and more, are all parts of the personalization experience.