What is the primary consequence of making abrupt changes in speed while driving?

Making abrupt changes in speed while driving primarily worsens potential skids because sudden acceleration or deceleration can destabilize a vehicle. When a driver makes sharp movements with the throttle or brakes, it can unsettle the vehicle's balance, leading to a loss of traction, particularly in adverse weather conditions such as rain, snow, or on icy roads.

This instability can cause the tires to slide or skid, which significantly increases the risk of losing control of the vehicle. Maintaining a steady and gradual change in speed allows the driver to keep the vehicle stable and within the friction limits of the tires, thereby reducing the likelihood of skidding.

In contrast, abrupt speed changes might enhance fuel efficiency or improve vehicle control in very specific, controlled circumstances, but these are not the general outcomes of such actions. Additionally, minimizing driver fatigue is more related to consistent, safe driving practices rather than rapid speed changes.