Winner
Diverse in Unity
I think you care about it more, hence why my posts are FULL of errors that i don't go back and fix. Why wouldn't you like to speak it all the time? (I'm monolingual so i can't compare to anything else)
I can think of several reasons.
1) There are things you just cannot express that well in two languages. Thus, if you were forced to speak one language all the time, a piece of your feelings would be untransmissible, you would "die a little" on the inside.
2) One's native language will always come more natural (unless the person hasn't lived very very long in a foreign country, which is not Winner's case), and easier to express. It's good to be able to relax every once in a while and not care about the way you speak.
3) You would lose the ability to communicate with those around you, since far from everyone around Winner or me speaks English. You would also lose the ability to read the literature of your country, everything that's been written as time went by.
It's quite a lot to miss...
What Mirc said, except the third point - I don't think Mowque meant that you'd forget your native language entirely.
Thinking in English - the process of conceptualizing - is harder. Plus, there are things which you simply can't say in English without losing a lot of the original meaning, which then "lost in translation".