Because sometimes, no matter how hard you try, the language barrier is just too much.
Like when you ask for a "gut-busting, laugh-out-loud good time" and the waiter just looks at you funny.
Or when you try to order "no capes" at a Renaissance faire and they just give you a puzzled look.
Or when you try to explain the concept of "Netflix and chill" to a grandma who just doesn't get it.