The reasons why drivers do not use turn signals when changing lanes can be summarized as follows: First, some drivers have operational inertia and consider signaling a redundant step, which is more likely to be overlooked especially on familiar roads or those with sparse traffic, such as community exits or suburban highways. Second, drivers with poor driving etiquette are self-centered, forcing lane changes or weaving across multiple lanes, completely ignoring the safety of vehicles behind. This behavior is particularly common at highway exits or congested intersections. In addition, some drivers choose to change lanes suddenly out of fear that signaling their intention will cause vehicles behind to accelerate and block them; this psychology is especially evident on viaducts or congested roads during peak hours. Many drivers have a cognitive bias about the function of turn signals, mistakenly believing they only need to be used in heavy traffic. Signaling 3 seconds in advance allows vehicles behind to predict and adjust their speed, which is actually more efficient than forced lane changes. Although traffic regulations clearly require signaling when changing lanes and set penalty clauses, the more critical point is to cultivate safety awareness. This simple action can reduce the lane change accident rate by 30% and is also a basic respect among road users. It is recommended that drivers develop the habit of using turn signals regardless of road conditions, while maintaining a safe following distance. When encountering vehicles that do not use turn signals, drivers should reduce risks through prediction and civilized reminders (such as flashing lights).
