A foreign coworker who had just joined the company asked me. "Everyone says '수고하셨습니다' when they leave work, but doesn't it mean 'you went through a lot of trouble'? Why does that count as a greeting?" Now that I think about it, he's right. I had never once thought it was strange. ## 수고 is 'the effort you put in' 수고 means the strength and heart you put into doing work. So "수고하셨습니다" means "I know the effort you put in today." In Korea, among people who worked together, recognizing the value of that effort is an important courtesy. That's why, when the day ends, "수고하셨어요" comes out before "thank you." ## Who sets the value? There's a hidden rule here. The one who judges the value of someone's work is usually the person above them. So if you say "수고하세요" to a superior, it can sound like a subordinate is grading them, or like you're telling them, "Keep working." That's why many people are careful about saying it to their boss at work or to their elders. That said, it's common to say "수고하세요" when leaving a shop. Everyone sees it differently, so just keep this much in mind. ## Saying it this way is safe When you leave work before others, you say "먼저 들어가 보겠습니다" (I'll head out first). When your boss is leaving, "안녕히 가세요, 내일 뵙겠습니다" (Goodbye, see you tomorrow) is a good choice. Even a single word carries weight, so if you pick the wrong one, your feelings may not come across as well. If you're not sure, greeting them with a smile is best.