I don't understand sheets. Our old sheets weren't deep enough for our mattress and bowed up along the sides so you could see the underlying mattress. So we went for deeper sheets and now it's all saggy up top and you can't keep a taut bed. That's fine visually (because I'm not that picky) but all the slack makes it easier to get tangled up in the blankets which is super annoying. But they work as sheets and I shouldn't penalize them because my mattress isn't as deep as I thought.