Cold feet

The phrase "cold feet" is often used to describe a feeling of nervousness, apprehension, or doubt that arises before undertaking a significant action or making a big decision. It implies experiencing a sudden lack of confidence or bravery, causing hesitation or withdrawal from a previously agreed-upon commitment or plan. This idiom is commonly associated with situations such as backing out of a wedding, declining an opportunity, or reneging on a promise due to fear or uncertainty.