What is considered unsafe entry onto a sidewalk or roadway?

Moving onto the sidewalk without proper signal is considered unsafe entry onto a sidewalk or roadway because it can create unexpected hazards for pedestrians and other vehicles. When a driver fails to signal before moving onto the sidewalk, they do not provide adequate notice to others about their intentions, potentially leading to accidents. Proper signaling is crucial as it communicates a driver's actions to nearby pedestrians and other drivers, allowing them to react safely. This practice is part of the rules governing traffic regulations to ensure safety and prevent collisions in shared spaces.

In contrast, the other scenarios involve different aspects of vehicle operation that do not directly pertain to signaling or the interaction between a vehicle and pedestrian areas, making them less relevant to the concept of unsafe entry onto a sidewalk.