During which situation is it most important to use turn signals?

Using turn signals when merging into traffic is crucial because it communicates your intentions to other drivers, allowing them to anticipate your movements. Merging is a dynamic situation where vehicles are often traveling at higher speeds, and the need for clear communication is paramount to maintain safety. By signaling your intent to change lanes or merge, you help prevent potential collisions that could arise from misunderstandings or sudden movements by nearby drivers.

In contrast, while signaling in a parking lot, at a red light, or on an empty road is still important for safety and compliance with traffic laws, these scenarios generally present less immediate risk and complexity regarding other vehicles’ behavior compared to merging into moving traffic.