Ever wondered why some of the best automotive achievements from Japanese carmakers never make it to Japan?

Take the world's first "boxer" diesel engine as an example. This motor, which features horizontally opposed cylinders instead of the standard vertical inline or "V" setups, powers the Subaru Legacy that just landed in European showrooms. But don't expect to see it in Japan.

Then there is the dramatically styled Infiniti FX50 sports utility vehicle (SUV), which Nissan CEO Carlos Ghosn unveiled at the Geneva Motor Show this month. That was an especially eye-opening event — one rare in modern times — because Ghosn introduced a new luxury brand name into Europe and announced a new Infiniti car . . . all in the same sentence. That's like introducing the Apple brand and the iPod at the same time. But as for the Infiniti coming to Japan, Nissan says it has no definite time frame as yet. If ever.