Modern headlights have become significantly brighter and whiter, but this advancement comes with a trade-off: increased glare for other drivers. From oil lanterns and acetylene lamps in the late 1800s to today's LED and HID systems, automotive lighting has evolved dramatically. Early headlights offered minimal visibility, but as speeds increased, regulations gradually formalized to balance driver illumination against glare for oncoming traffic.

Today, LEDs and cooler color temperatures produce more concentrated, blue-white light that appears sharper but causes more discomfort, especially in rain or on poorly marked roads. The rise of taller SUVs and pickups compounds the problem, as higher-mounted headlights shine directly into smaller vehicles. Adaptive matrix headlights aim to solve this by selectively dimming portions of the beam, but adoption remains inconsistent.

According to 2019 to 2023 Fatality Analysis Reporting System data, 46,154 fatalities on US roads occurred at night and in non-lit areas, with 446 attributed to glare impeding a driver's vision. California, Texas, and Florida top the fatality lists, consistent with their large populations and vehicle miles traveled.