Why should car drivers not move into the same lane as a motorcycle?

Motorcycles need a full lane width to operate safely. Unlike larger vehicles, motorcycles can be more affected by road conditions and obstacles. By requiring a full lane, motorcyclists have the space they need to maneuver effectively, particularly to avoid hazards or maintain stability. If a car driver were to encroach upon this space, it could inhibit the motorcyclist's ability to safely navigate the roadway, thereby increasing the risk of an accident.

While other factors, such as the stability of motorcycles compared to cars and their right of way in certain situations, play important roles in roadway safety, the critical issue with moving into the same lane as a motorcycle is the need for that full lane width to ensure safe operation and minimize the danger of collisions.