Mine changes. Blue used to be my favourite colour. Then it was browns and yellows. Then it changed to greens. And now my favourites are more deep oranges and rust colours.
I have always been in love with green, since I was a child. I love all shades of green and find them calming and soothing. Even my eyes are green! I have always believed that favorite color has a lot to do with your physical makeup because people feel so strongly about them!