Why don't you hear Korotkoff sounds when BP cuff is not inflated?

Korotkoff sounds are the noises made by the blood flow in the arteries when a blood pressure cuff is inflated and then gradually deflated. When the cuff is not inflated, the artery remains open and blood flows freely, resulting in no turbulent flow or sound. It is only when the cuff pressure temporarily occludes the artery and then allows for intermittent blood flow that these sounds are produced, indicating systolic and diastolic pressures. Without inflation, there is no restriction to create the conditions necessary for Korotkoff sounds to occur.