Just like we fluff our pillows before we go to sleep, in nature they look for the sweet spot in the grass or the leaves. They just brought that behavior with them when we brought them in the house. It is really fun to watch her with that when we rake the leaves in the fall.
It is fun to watch, she does it every night, she scratches the floor near her bed, then she circles around three or four times before curling up on her bed. Sometimes she gets up again and repeats the whole process.
It is the little things like they do that make us love them so much. Those circles are usually followed by a big flop and a heavy sigh around here. She is such a drama queen. Maybe she just wore herself out by circling her bed first!
I haven't noticed my cats doing it except when the use their tray, they take time to choose exactly the right spot. Come to think of it Lucy is rather picky about the spot she chooses too.