Im still surprised on how we dont see yet at least one good player from the whole south asia and even including India we still didnt see any good player for there, im not expecting a whole national team making good steps towards becoming a contender to be in the next world cup, but at least to see 1 between so many millions reaching europe.
How can they be this bad?
I guess it's mainly because football is not the main sport. Sometimes we see things from a European/South American point of view, where there is football, more football, and more football again, and then some other sport. I don't know a lot about sports in India but I guess that cricket is way more popular than football; same goes with China where they focus more on individual sports rather than teams. Japan for example have been investing a lot of time and money promoting football because until 20-30 years ago it was not very popular and I think that still nowadays baseball is more popular than football.
Improving a national team requires decades of work because you have to create and grow a few generations of players, it's not something that you can do in a few years, it requires a huge amount of organization and planning.