It's not a Roomba but a Robomaid, which does much the same thing.
The practical upshot of the fatigue brought on by processing all the extra sensory stuff that normal brains filter out is that my house is usually a bit of a mess. I just don't have time or energy to keep it as clean as I'd like. I only have energy to do so much, and sweeping up cat hair is a fair way down the list.
But I really really really really don't like dirt. I want my house to be clean.
I thought about employing a cleaner, but just don't want to. I don't have hangups about employing someone to do something I "should" do myself, I just think that it'd be one more thing I'd have to organise and remember and another interpersonal interaction to deal with, and it'd create a new hassle to replace the one it solved.
A robot cleaner, on the other hand, works pretty well in two ways.
It literally does a good job. It produces a lovely clean floor, and a clean floor goes a long way towards making the whole house look and feel clean. But it's also helping me get the rest of the work done...
I don't trust it enough to switch it on before I leave for work, because it does have trouble finding its way out from under the couch and is frightfully confused by a five millimetre step in the lounge room. Instead, I'll set it off to do the floors while I bustle about folding laundry and putting it away, returning errant cups to the kitchen, and generally being useful. Knowing Ruby (she's red, OK?) is at work on the floors makes it easier to motivate myself to do the rest. It's like the 90 minutes Ruby runs is Dedicated Cleaning Time, and when she gives up and slides back into her cradle, I can call it a day as well.
So yes, the floor's clean. And from the skirting boards up is... well... I wouldn't say 'clean', but it's cleaner than it was.