Think about it. If you have 1.4 billion people who are mostly interested in cricket only, as cricket is the top sport in the nation, it means you have intense competition for professional teams and from all the pro cricketers in the nation, you cannot produce 11 who can win major tournaments against the likes of australia, population of 26 million, where cricket is not even the only sports and the interest in the game is divided between other sports. Besides, they dont have the same amount of money that India has. I think the population and overall interest a sports has in the nation has a huge huge imapct on the success of the nation. Look at US, and its dominance of basketball and baseball over the years.
its simple probability really.
India may be populous but it ain't a rich country, per capital spent on sports would be miniscule compared to the countries proficient in sports. Well who am I telling, i doubt you would understand such things but lemme give it a last shot. If population size and it's interest level could determine wold champions then since 1975 every final should have been between India and Pakistan.