I actually just don't understand why one person picking up 10 loads of different people's laundry, doing the laundry, and delivering back the folded loads requi

I actually just don't understand why one person picking up 10 loads of different people's laundry, doing the laundry, and delivering back the folded loads requires less total minutes of work than 10 people doing 10 loads of laundry at home. Yes, it takes less people, but those people spend their lives doing laundry. Yes, servants are specialized workers. I think there may be marginal efficiencies over people taking their clothes to a laundromat in some cases. But I've never heard of anybody with washer and dryer at home using a laundry service. Typically they'll just hire a maid to do their laundry if they really need it.