The curiosity, the impression you get from a language you heard normally attract us to learn language. For example I learnt Spanish because I like to hear interview of one my favorite racer, Dani Pedrosa and I was so curious to know and understand what he talked about without needed to see subtitle. Or I learn Russian because It sounds beautiful in my ears.
So, different motivations could encourage you to learn languages
You can chat with a foreigner.
I think that it is interesting when you are learning a new language, because you will be able to speak with people of other countries and you can also know their culture. It is an interesting way to know the culture and you can find new friends.