I still don't get the point. The washing process takes only one hour? I just put everything inside, stay there and play a niche.tv video and voila, everything is clean. At least at the moment it doesn't matter if you wash your clean clothing a thousand (or more) times.
I do get however that one might want to wash just some selected pieces. Like just *some* stained but not all. So you can wear all your favorite, unnecessarily stained, panties while selling all the others stained ones to the perverts.
And tbh, I also would like the clothing getting dirty, not necessarily stained, after wearing it for a while. If this was the case and wearing dirty clothing would cause some reaction (which to my knowledge it doesn't atm), and if the capacity of the washing machine was limited, *then* selecting which pieces to wash would be 100% justified.