quick to seize an opportunity
A set phrase describing someone who is alert and acts swiftly when a chance arises. Often used as a な-adjective to modify a person or attitude.
彼は機を見るに敏な人で、チャンスを逃さない。
He is quick to seize an opportunity and never misses a chance.
ビジネスでは機を見るに敏であることが大切だ。
In business, it is important to be quick to seize opportunities.
A classical set phrase combining 機 (opportunity), 見る (to see), and 敏 (quick, sharp). The exact origin is uncertain, but it follows a common pattern of Sino-Japanese expressions describing astute behavior.