You always want to have the image loaded before you actually use it. You don't want to wait until you actually use the image. For instance in a carousel, you'll want to load the next and previous image, not just the current displayed one.
I'd much rather have a "loading order" than lazy loading. Sure, I don't want to load first the big images that I'll want to display later, but I definitely don't want them to appear while I scroll down...