Segway

The Segway cost $4,950 at launch but produced only 80 units per day, yielding just 100,000 total sales in its first six years—far from predicting an urban revolution. Its gyroscopic balance impressed, but the lack of infrastructure and bulky design limited it to tour groups, while $500 electric scooters later succeeded by being 85% lighter and offering similar range. Segway remains a textbook case of overhype, with a price 10 times higher than typical mobility alternatives but 50% worse performance in speed and portability.