According to J.D. Power, Toyota's Tahara plant in Japan is, for 2 years running, the best-quality auto plant in the world. No, this isn't the factory that builds the IS (that would be the Iwate plant of Kanto Auto Works). Tahara builds the Lexus LS and GS models, as well as Toyota's Crown, Celica, RAV4, and Land Cruiser.
These excerpts from the article are particularly interesting: "Rival luxury automakers may murmur that Lexus cars are merely “souped-up Toyotas” because the two brands share a wide array of parts. But suppliers to Toyota know better. Toyota, already a stickler for quality, will not accept components if defects exceed 50 per million parts shipped. In contrast, for Lexus vehicles, Tahara managers insist on fewer than 10 defects per million parts. From the outset...(it was) established that the margin for error for Lexus vehicles would be half what it was at Toyota. On average at Toyota, air leaks from car exhaust systems are held to 100 liters per minute, to reduce noise. On Lexus models produced at the Tahara plant, the ceiling is a stingy 8.6 liters of air per minute."
Click here for the full article. Our thanks to The Chief for providing supplementary information.