Thanks for your hard work — the all-purpose workplace greeting.
Said when leaving the office, when a colleague finishes something, when you pass someone in the hall, and when a project ends. It functions as hello, goodbye, thank you, and well done all at once. お疲れ is the casual clip.
Do not translate it as "you must be tired" — that reads as odd. It acknowledges effort, and Japanese offices run on it.
Reading a definition isn't the same as saying it to someone. Lingo Kaiava is a voice tutor set to Japanese — it uses お疲れ様 the way locals do, corrects you in the moment, and never "fixes" the way real people actually talk into textbook Japanese.
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