Why do you study language?

Almost every Sunday morning, I talk with an American friend on Skype. We met a language exchange site, Lang-8, this march. He's learning Japanese all by himself for several years.

He lives in Florida and he is nice, funny and a little bit shy. Every Japanese learner has their own reason for studying Japanese like Japanese culture, manga, J-Pop and so on. He said he likes the sound of Japanese. I understand his reason that brought him to learn Japanese because I also like the sound of English.