I asked a 4 year old kid of my kinder class today: 何で英語を習いたいの？

He said first 分からない and then I asked again and he replied: "だって英語が分からないんだもん".

This kid is badass. So, when someone asks me now why are you learning Japanese I'll know what to say.

I've always been pretty content with "because I want to understand Japanese". That way, if the person is interested enough to ask "why", I can fall back on "because I want to"

Generally speaking, everyone I've run into that knows I'm learning Japanese, is either uninterested, thinks it's a waste of time, or things Japanese is meaninglessly complicated. Needless to say, in Australia, the majority of people can be pretty outspoken about the fact "English is what we speak", if forced into a situation which brings about the question of other languages/cultures.

So what will you say when they ask why you're not learning Swahili?

@Stansfield123 Depends on how close I'm to the person. Some options are: "fück you"; start crying and freak them out; "I know Swahili".