My little girl loves "things that sink", she'll sleep on top of her pet carrier if I let her, on handbags, school book bags, on blankets or towels that are on a rack to dry, anything that sags a bit under her weight she just loves.
So I got a cat tree with a hammock JUST for her (because my big boy is too big to fit in it, and she's a bit spookish, so I wanted her to have a safe place that was just hers to go to).
So of course she loved it for about half a day, and then ignored it entirely for 3 months. Until this week, when she's suddenly decided it's the bestest bestest place ever (leading to big boy trying to sleep in it too, and promptly falling out on his head. Twice. )
Cats do what cats do, ours not to wonder why.
I actually suspect, now that the winter dark is lifting, and it's by a big picture window, it's just more interesting now as a place to go to the cat movies, otherwise known as watching the neighbours birdfeeder.