My two year old is very clean when it comes to his stall. He always leaves his presents in the left back corner of his stall. Before we really started renovating the barn it there used to be a two sided heated water machine thing lol, (for him and my other pony next to him) in that corner so he'd always poop in that.
It was disgusting. And every time I'd finish cleaning it out he'd go over, investigate, then snort as if it wasn't to his satisfaction lol.