True enough. If, however, >>1 really becomes a doctor, most of that won't matter. Whether that's right or wrong, well...that's a whole different question.
Anyway, I think it's a good goal to have, even if it is a little unusual to want to practice in Japan. Even if >>1 decides not to go to Japan, he/she will still have a solid career. Intentional or not, having the foresight to consider a "backup" plan is definitely a good thing.
Incidentally, >>1, where do you live? There are a lot of places that need more hospitals and more doctors.