好こう機きを逃のがす

expression, godan verb (-su)

miss a golden opportunity; let a chance slip by

Used when someone fails to take advantage of a favorable moment, often with a sense of regret.

• 彼かれは好こう機きを逃のがして、昇しょう進しんできなかった。

  He missed a golden opportunity and couldn't get promoted.

• 好こう機きを逃のがすな。

  Don't let this chance slip by.