They don't need to be anywhere near as efficient or effective as me, they just need to be able to do it unattended. Roomba is a great example - it's great to be able to have floors cleaned every day while I'm working, even if it takes 10x longer to do so. If a robot could do laundry while I work, put away the dishes from the dishwasher in the morning, and mow my lawn while I'm BBQ'ing, it's a life changer.