“Double down” comes from blackjack, where you double your bet hoping your next...

https://juliussbrilliantchat.lowescouponn.com/double-down-vs-commit-to-a-decision-untangling-business-english-from-the-casino-floor

“Double down” comes from blackjack, where you double your bet hoping your next card seals the win. In English, it means to commit even more strongly to a risky choice. Common slip: learners think it means to undo a bad call—it doesn’t