In this case I wouldn’t associate the poor usability with the designers, I think its down to big business not caring. Plus it costs more to make a UI good, and flexible for different user situations. They’ll also hire the cheapest designers. It’s all about saving money and more profit. Their main aim. And in the case of monopolies, people can’t go elsewhere. The problems all come down from the top.
Me in shop: I want to buy a robot vacuum cleaner. Do you have one of those sweary ones?