What brought you to Korea in the first place?

source : 오늘의 표현 13: '어떤 계기로 한국에 왔어요?'를 영어로!

He was wearing the same clothes as yesterday. ㅋㅋ
and he said, "I hope you can look past that."

계기 (motivation)

What was your motivation to begin studying English?

Why are you in Korea? (could be rude!)
-> What brought you to Korea in the first place?
in the first place : 애초에, 처음에

What got(made) you interested in Korea in the first place?
어떤 계기로 처음 한국에 관심 갖게 되었나요?

How did you two meet in the first place?
We're college friends. / We're old college buddies.

We should've more aggressively opposed this in the first place.
We should've done more to stop this in the first place.