Last month, after a dust storm shut down Interstate 15 between Las Vegas and Barstow, Google Maps sent drivers off-roading, rerouting them via barely passable desert trails. Some were stuck for hours. Google has since apologized.

Jalopnik describes this as yet another case of blindly following, but I think this is a more specific failure mode. Rerouting due to road closures or traffic jams opens up routes that the algorithm would normally deprecate, and catches more drivers unprepared. It’s one thing when that means a quiet residential street gets an expressway’s worth of traffic, quite another when the second best choice is a dirt track—or a 500-mile detour. When the best answer the algorithm can give you is a bad one, it will still give you that answer.

Previously: Man Dies After Driving Across Collapsed Bridge, Family Sues Google; Google Rerouted Traffic Up Poorly Maintained Mountain Roads During a Blizzard; Google Maps Called Out for Showing ‘Potentially Fatal’ Mountain Routes.