Well, firstly, not every robot needs to carry a lot of weight or run for prolonged periods of time without recharging. Not every robot will be built the same. And the ones that are built that way will probably be designed well, so they're not disposable like cheap phones. Robots that replace manual labor should do what we do and use machinery/tools instead. They just need to be very efficient and flexible at moving in the physical world, not hyper strong. But yes... there is a big problem that working with your hands will still be cheaper in back breaking labor, for a while. I was just saying we don't need batteries that last for days without recharging, since we can build the world around recharging. There are already automatic vacuum cleaners that recharge themselves. Also, recycling is going to be more important in the future.