- Reducing aerodynamic drag improves fuel efficiency by allowing air to flow more smoothly; the faster air flows over a vehicle, the more drag is created. By strategically placing a spoiler at the rear of the car, it can help to divert air away and reduce the amount of drag.
- Increasing traction enhances stability, especially at high speeds. As air flows over the car's body, it creates a low-pressure area over the rear end, causing it to lift. This can be counteracted by the downward force generated by a spoiler, which helps press the rear wheels down onto the ground.
Spoilers can also enhance a vehicle's appearance and personalize its design.