What should NOT be used when road conditions are poor?

When road conditions are poor, drivers should avoid using cruise control, as it can lead to loss of vehicle control on slippery surfaces. Additionally, using summer tires in snowy or icy conditions is inadvisable, as they provide inadequate traction. Lastly, aggressive braking or acceleration should be avoided, as it can cause skidding. Instead, drivers should maintain a safe speed and increase following distances to ensure better control.