It's all about warranty deniability.
I've never owned one, but my instinct about them is a robot will clean better than a vac. That seems obvious. And it'll brush, too. That's big. My dealio:
1. I don't like the idea of the cord laying on the deck.
2. I don't like the idea of having to monitor how much dirt/leaves have been collected.
3. I don't like the idea of having to empty the thing out periodically.
4. I already bought, and so now own, a vac!! (Before I even knew anything about robots.)
For the entire off season (about six months, unfortunately) I don't have to think about how my pool gets cleaned. Nothing to check on or empty or put in or out of the water Nada. And from the house I can't really see the vac's hose (a robot's cord would bug me).
I've yet to clean my filter cartridges, so whatever is getting to the filter via the vac is not causing me significant extra work. I do have to clean the pump basket, so there's that. But I don't have to haul out a 50lb robot to do that. More importantly, I can glance at my pump basket and know to empty it or not. I don't have to wonder if it's full or not, or drag the vac out to determine that.
So for now, the Rebel fits...
I wasn't really joking about the charging garage. The technology already exists (cordless, finding the pool, finding the garage, etc). The challenge would be how the thing would get in and out of the pool. A ramp? A second component that drives the robot around on the deck, and can hydraulically lower it into the retrieve it from the water? A garage built into the side of the pool? Some sort of spider legs that can walk up steps?
All that would be needed would be for Pentair (or some big player) to sponsor a few episodes, maybe a season, of
Robot Wars, call it Robot Wars Marine or something, and let those nerds figure it out!:splash: