Excellent article, but trying to separate Kia from Hyundai doesn’t really work. They share too much common tech between them. In many cases, the underlying vehicle is almost just a stylistic difference with the core platform, engine, EV battery, transmission, etc., all from the same factories, and they even have the exact same part numbers. In some cases, they even share the same body and are just badged differently. Kia and Hyundai are both brands under the Hyundai Motor Group, and much like the dozen different brands (Buick, Chevrolet, etc.) under GM, they operate separate design, engineering, and marketing, but they don’t operate independently. Kia is a subsidiary of HMG. In fact, as you point out but still somehow miss, the entire reason why Kia’s quality went up is because of Hyundai's majority purchase. “Quality” differentials between Kia and Hyundai as brands are as non-sensical as making quality differentials between different product lines by any car manufacturer. Every car manufacturer has higher and lower quality lines because that’s how different things bring different works. In particular, this is true when new designs are introduced. If you look at the product lines developed by Kia and Hyundai, the underlying components are first developed by and used by Hyundai and then picked up by Kia. Kia has higher reliability simply because it almost always uses already-proven components. Kia engineers are building with essentially a catalog of parts that have already been in use. This is also why Kia tends to be slightly cheaper because Hyundai keeps the majority of hard R&D costs on its own books while both Hyundai and Kia benefit.