가는 날이 장날이라더니 · 가는 날이 장날이네요
of all days, bad timing (lit. the day you go happens to be market day)
Example
가는 날이 장날이라더니, 맛집에 갔는데 하필 쉬는 날이었어요.
Talk about bad timing: I went to that famous restaurant, and of all days it was closed.
Word parts
장 market
You travel to visit someone, and it turns out to be market day, so nothing goes as planned: everyone is out or the place is packed.
Good to know
Pronounced [가는 나리 장날]. Today it almost always means unlucky timing, like finding a shop closed the day you visit. Often paired with 하필 'of all things'.