It doesn't need the build quality, but it should. Build quality is what killed the American auto industry in general. Where do you think the rep of unreliable and crappy came from? They really do make crap cars. We like to joke about Hyundais and other cheapy cars like that, but to be honest, the build quality in a Hyundai now is threatening the Japanese. Certainly blows away the basic American car. Sure Hyundai doesn't make as much money by increasing it's build quality. However, for a newer company like them, it's more important for them to establish a reputation as a car you can count on. Like the Japanese did.
The domestics are now in the same situation (rep wise) that the Koreans were about 10 years ago. They still sell a ton cuz of rentals and blind patriotism (also big trucks/suvs), but they need to adopt the attitude that they're underdogs and offer more to the consumer in order to gain their rep back.