It's the 21st century. There are some technologies you'd think we would have by now. The one most people think about is flying cars. We don't have (readily available) flying cars. But I think that's probably for the best -- we can barely handle the non-flying kind.
But the technology I don't understand why we don't have is a machine that will wash clothes and then dry them. We've had cars for less than two hundred years. But we've been washing and drying clothes for millennia. It's a problem that affects almost everyone--poorest to richest.
You should simply be able to put in your dirty clothes in one machine, have them be washed and dried and then come out clean. It's a simple concept, so why don't we have them yet?