Surely you've noticed that nobody has servants anymore. It used to be that members of the middle-class had household servants. A maid to clean, and a cook to, well, cook. Why has that job nearly died out? Well, for one, people don't want those kinds of jobs anymore. They can get other jobs that pay more (there's an economics lesson there that I'll leave for another day).
For another, we have technology which eliminates those jobs. Household robots. These robots started off pretty stupid, e.g. a robot which would stir a bowl forever at whatever rate the cook set it at. Or a robot which would peel and core an apple just by turning its crank.
What can we learn from the existance of these robots? Mostly, you're seeing the effects of capital formation. Back when everything had to be done by banging two rocks together (e.g. laundry, food processing, knife creation), you had to spend a lot of time banging those rocks. Some people found that specialized rocks did a better job. To find or create these rocks, they had to take time out of doing their job. They needed to be able to give up current consumption to create a greater efficiency. That's capital. Tools are capital.
Of course, if it's not your effort, you don't care quite so much about making it efficient. Not, that is, until the end of the month, when you have to pay for the effort. At that point you have to consider: do I continue this consumption, or do I do without for a while, save my money, and buy a machine to do this job?
Some economic illiterates will, at this point, say "But you're talking about putting that person out of a job!" No, I'm not. I'm talking about putting them out of *that* job, not every job which they might possibly perform. There are some jobs which are so tedious that nobody wants to do them, e.g. scrubbing a floor, or handling garbage. We now have floor scrubbing and vacuuming machines available at a reasonable price. There is no machine for handling garbage that I've heard of. No doubt multiple inventors have created them, but human labor is still cheaper than the necessary capital.
Specifically, iRobot has created the Roomba vacuuming robot. The key to its success, besides its cuteness and its efficacy, is its price. They have brought the price of a robotic vacuum cleaner down to the point where a lot of people value $200 less than their time spent doing all the vacuumings that a roomba can do over its lifetime.
irobot's next product should be a mini-zamboni for clearing and cleaning pond ice. It can cost 15x what the Roomba costs. Call it a Zoomboni. There's an attachment for your John Deere lawn tractor for cleaning pond ice, but what lunatic parent wants to be out there in the cold running a lawn tractor around on the ice?? But to be able to buy a robot that does it while you're sitting inside the house? Now that's worth money.
Of course, it could fall through the ice. Yes, no question. But if it's gonna, then you were gonna, and why were you so foolish as to consider going out on that ice much less sending a valuable robot out on it? But yeah, somebody will do it, so a retrieval tether is a good idea. If you had two of them, the Zoomboni could tell where it was on the ice, which is also a necessary characteristic. Probably can't use Roomba's random walk and wall-following algorithms.