I've been to five very different countries and I must say, this is pretty much true. However, that said, there are two different ways of being terrible flirts. One would be that they are too scared to at all and another would be to say that they have the bravery, but no talent. After living in Korea for a year, I can safely say that Korean women are MUCH better than American women when it comes to the former, but much worse in the latter. Keep in mind though, I am very difficult to flirt with. Korean girls tend to use the "full on flattery" mode much like American guys do and I absolutely cannot stand flattery.