how come?

Idioms  

1. How is it that, as in How come you're not attending the conference? Sometimes how come follows a statement and asks the question “why” or “in what way,” as in You're not going? How come? The related phrase how so? functions the same way, as in You say she's changed her mind—how so? How come is short for how did it come about that and dates from the mid-1800s; how so, short for how is it so or how is it that, dates from about 1300.

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Example Sentences

“How come we have had a Perseverance Rover on Mars for years, happily sending data back, and we haven’t had an autonomous rover in the Arctic?” said Saunders.

From The Wall Street Journal

If we’re so unaffordable, they said, how come we pack our stadium every night?

From Los Angeles Times

“Have you noticed how much rain they get in the future now? Everything is rainy and muddy. I don’t understand, either, how come everybody is so dirty when there’s so much water around everywhere,” Gerard observed with what seemed to be a healthy sense of humor.

From Los Angeles Times

How come no one talks about the opposite—about a “smartogenic” society?

From The Wall Street Journal

“How come this sand is so much more … normal than the Sands of Asase?”

From Literature