Why does the time keepers start the timing when they see the smoke not hear the shot?

Timekeepers start timing when they see the smoke rather than hearing the shot because light travels faster than sound. This allows them to accurately gauge the moment the shot is fired, as the visual cue of smoke indicates the exact instant of ignition. By relying on sight rather than sound, they ensure precise timing, which is crucial in many competitive contexts, such as racing or shooting events. This method minimizes any delay caused by the time it takes for sound to reach them.