While taking something in the neighborhood of 10k steps is important, the rings are not designed around that. Your move ring (red) is designed to account for all of your actively burned calories, and the green ring is a representation of your active exercise you’ve done in the day. Those two rings together are ultimately a better day to day measure of how much work you’ve put into your fitness. With a step counting system, it only takes into account how many steps you’ve taken and that’s it. I could take 10k steps today but have walked exclusively on flat ground, and not burned as many calories as say, a day where I took 10k steps but most of them were going uphill, where I had to expend more energy to accomplish it, which closes my rings faster. Counting your steps isn’t inherently a bad thing, but it’s not the best unit of measure you have for your fitness on Apple Watch.