Deer run in front of cars primarily because they are startled and confused. They often do not realize how big or fast cars are and may run instinctively in what they think is the safest direction, which can sadly be right into traffic. Other reasons include being temporarily blinded or disoriented by headlights, mating season behaviors causing increased activity and recklessness, habitat disruption forcing them closer to roads, and their natural flight instinct that leads them to dart unpredictably when scared. Young and inexperienced deer and those trying to cross roads to get to food or shelter also contribute to this behavior. This combination of fear, confusion, and distraction often results in deer running in front of cars unintentionally.