What happens to traffic flow during major traffic incidents?

During major traffic incidents, traffic flow often comes to a halt due to the presence of blocking vehicles, debris, or hazards in the roadway. Incidents like accidents or breakdowns can create bottlenecks, causing vehicles to stop entirely. This stoppage can lead to significant congestion and delays, not just at the location of the incident but also in surrounding areas as drivers slow down to assess the situation or navigate around it.

In contrast to the other possible outcomes, which suggest that traffic would either improve or flow normally, the reality during most major traffic incidents is that disruption is a key factor. Unpredictability can indeed arise from the situation, but the most direct and immediate effect is often the complete cessation of movement, particularly as response vehicles enter the scene or as drivers are required to stop to ensure safety.