Thoughts about local men finding overseas girls?

No judgement here but just curious. We seen most local men finding different nationality girls because they couldnt find a local girlfriend (maybe). And this seldom happen to local girls if they couldn't find a local boyfriend. They wouldn't go and seek for a different nationality guys and rather stay single (have, but rarely).

Why is that so?

And genuine question for the guys, why would you all prefer a different nationality girlfriend rather than local girls? Why wouldn't you guys wait and stay single till you found "the one" locally, but prefer to seek somewhere else?