Another thought, coming back from the field today. Roomba can of course free someone from some vacuuming’s task. Nevertheless, it might lead to supplementary efforts around vacuuming as well: e.g. tidying up the room beforehand (putting away the kids toys, putting chairs on the table), building up walls for the Roomba so that it doesn’t go anywhere.
The adoption of Roomba might depend on this weighting between: how much supplementary efforts does it represent versus how much benefits does it bring.
Another hypothesis to investigate further.