“Double down” comes straight from blackjack—when you’re so confident, you...

https://idiominsider.com/talking-odds-at-work-the-risk-idioms-every-english-learner-gets-slightly-wrong/

“Double down” comes straight from blackjack—when you’re so confident, you double your bet after the first two cards. Language learners often think it means just “try harder,” but it’s actually about risking more when the odds feel right