take the wind out of someone's sails

The phrase "take the wind out of someone’s sails" is an idiomatic expression that means to deflate or diminish someone's enthusiasm, confidence, or momentum. It typically refers to a situation when someone's excitement or optimism is suddenly diminished or undermined, causing them to feel deflated or discouraged. It suggests removing the person's source of motivation or energy, much like removing the wind that powers a sailboat, leaving them feeling disheartened or demotivated.