소 잃고 외양간 고친다

so ilko oeyanggan gochinda

Word for word

“Fixing the barn after losing the cow.”

What it means

Taking precautions only after the damage is done.

When you'd say it

When a fix arrives too late to matter.

Closest English saying

Locking the stable door after the horse has bolted.

Example

해킹당하고 나서 비밀번호를 바꾸다니, 소 잃고 외양간 고치는 격이네.Changing the password after the hack — fixing the barn after the cow's gone.