Just as one puts on one's headband, the state examination ends.
Used to describe a situation where an opportunity has expired just as one finished preparing to take advantage of that opportunity.
Koreans have a tradition of wearing headbands as a symbol of their determination to overcome a difficult situation or to win a difficult struggle, such as workers striking for better pay and conditions. Students preparing for difficult state examinations in both old and modern Korea have also been known to wear such headbands to show their determination to pass the exams. Phrases such as "certain victory" are often written on the headbands.
Too little, too late.
Muddle away one's opportunities.
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