There was a time when India had just opened it's market to the world (somewhere in early 1990s). All the international companies were trying to get their lion's share in the populous Indian market. That's when most of the Miss Indias started to win the international pageants. This helped those huge international companies to have international but still Indian figures to launch their products in India. That is why there were so many winners all of a sudden ... and then the situation went back to how it was pre-open market (i.e. no one cares about Indian beauties any more).
This is a theory popular in economic circles .. it could be wrong but I guess there is some truth in it.
Now a days, most of the Indian actors are used for launching international products .. there are no great models or anything.
Bollywood gave chances to the well known faces ... and now that trend has slowly slowly declined because the number of known faces have been declining too.
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