1. It occasionally doesn’t properly return to the home base, because it’s hard to find a good place for the home base where it can’t be moved/knocked over accidentally. This happens maybe once every 2 or 3 weeks, and is just a mild annoyance: you just need to carry the Roomba to its home base yourself.
2. After 3 years of usage, the battery died in such a way that it emptied rapidly enough for the Roomba to not be able to return to the home base. This was easily fixed by installing a new battery.
I recently upgraded to the Roomba 980, and it seems to work better than the 780 — it cleans more quickly and returns to its home base more reliably. Also, less cleaning required due to a different brush design.
Overall, I feel that I’m definitely getting my money’s worth out of the product, and it’s doing a great job at vacuuming. YMMV, but for me, it’s great.
>Say $30 an hour
Depends on where you live. Around here (CE Europe) I get cleaning service for ~5$/h (~15$ for 3 hours of work once a week).
Can I personally clean the foors better? Yes. Can I personally clean my dishes better? Yes. Dishwasher sometimes turns things upside down, doesn't clean properly etc.
But the main reason is that it saves me a lot of time, and it's good enough for me. Maybe not for you.
My anecdata: we've had three since 2009, the earlier ones cleaned well but got dirt inside and eventually stopped working after 2 years. Our latest one bought 3 years ago seems better designed and more reliable, zero problems so far. Ours runs 2-3 times a week, mostly on wood and linoleum floors, and fills up with pet hair and dirt each time. We don't fiddle with the IR barriers, we just put a box in a doorway if we don't want it to roam, and we don't worry about docking, we just pick it up wherever it stops, empty it and dock it manually. Overall, it does a good job of getting most of the dirt in an area, but there is still the need to do a deeper clean once a month. Not affiliated, just a satisfied customer.
But our Roomba was a miracle worker when my wife was laid up in bed for 6 months with a shattered pelvis and I was also extremely sick. And while I know how, and have time, to weed my garden, this robot could help people who don't have the time or energy to keep up with such thing. And the stories don't even have to be that dramatic - in a family with 5 kids, there are better ways to spend time than vacuuming carpets.
Sometimes having devices like this isn't about the quality of the work - it is just about the work getting done at all, so your time can be spent on more important things.
It's not replacing a normal vacuum, anyone who thinks so is fooling themselves. It's to keep your house cleaner in between normal deep cleans.
> "Some 15 million of them are cleaning floors all over the planet, and they’re doing so reliably and affordably and autonomously enough that people keep on buying them"
It is absolutely not "reliable". It's barely better than cleaning the floor myself. Some days, cleaning the floor myself would actually be easier, or ends up being what I have to do anyway. The number of issues I've run into with the damned thing is absurd and I feel like they should be fixing those before making a new product.
I think people are for the most part getting tricked into buying these. They're not that great.