What driver action can cause a bicyclist to lose control?

A driver making abrupt lane changes or turns without signaling can cause a bicyclist to lose control, as this unexpected maneuver may force the cyclist to swerve suddenly to avoid a collision. Additionally, drivers opening car doors into the path of a cyclist, known as "dooring," can lead to serious accidents and loss of control. Other factors, such as speeding or aggressive driving, can also create hazardous situations for cyclists.