"If you talk to a man in a language he understands, that goes to his head. If you talk to him in his language, that goes to his heart."

~Nelson Mandela

Several years ago I started watching Korean dramas and reality shows, but I always had to watch them with subtitles. When a new show would air in Korea it took almost a week for a subbing team to have subtitles in english. So I decided that it would be amazing if i could watch all my shows (immediately after they aired) without the use of subtitles. So thats why I orginally wanted to learn korean. Now, however, my interest in learning Korean is much more than that. I have personally fallen in love with the culture and the ability to speak the language allows me to really connect with Korean people and learn more about the culture. :)

I'm a programmer and I enjoy learning new programming languages so I though I would try learning a new human language. :)

As for me, I started learning English because it is really useful almost for every side of my life. I made up my mind to start studying two years ago when I realised that knowing English you can earn 20% more at the same position at work. Nowadays, we have a lot of expats who work on high positions for the world giants like CocaCola, Pepsi, Microsoft and so on. If you can communicate with them fluently you will be able to get closer to them and perhaps obtain a better position. 

The other bonuses you can get are watching original versions of Hollywood movies,  talking to people all over the world,  reading books and articles on the Internet,  etc etc etc

It is very interesting. 
English may not be the most spoken language in the world, but it is the official language in a large number of countries. It is estimated that the number of people in the world that use in English to communicate on a regular basis is 2 billion!
The English language is the most important language, and I would give my eye teeth to speak in English fluently.