flash in the pan
曇花一現（沒有長久效果或持久影響的事物）
口語·形容曇花一現
英文釋義
Something that initially shows great promise or potential, but ultimately fails to deliver or live up to expectations
例句
His singing career was just a flash in the pan; he never made another hit.
典故來源
源自18世紀火槍術語，火藥池中的火藥閃光（flash）卻未引燃子彈（pan），比喻短暫成功無后續。