What can reduce the effectiveness of a traffic control plan?

A traffic control plan is crucial for managing the flow of vehicles and ensuring the safety of both drivers and workers in construction zones or areas with altered traffic patterns. Poor maintenance and lack of visibility in traffic control devices are significant factors that can undermine the effectiveness of such a plan.

When traffic control devices, such as cones, signs, and barriers, are not properly maintained, they may not function as intended. For example, faded signage or damaged cones can lead to confusion among drivers, preventing them from understanding the necessary actions to take in altered traffic conditions. Visibility is key to ensuring that drivers see and respond to these devices effectively. If they can't easily see signs or if devices are obscured or lying on the ground due to poor maintenance, the traffic control plan fails to guide drivers adequately.

The other choices also present valid points regarding factors that can diminish the effectiveness of a traffic control plan, but focusing specifically on maintenance and visibility highlights how these practical aspects directly influence the plan's success in real-time traffic situations.