As with any new application of technology, it was unclear whether the Prius--and hybrid cars in general--would have a lasting impact or simply fizzle out.
The Prius has obviously withstood the test of time, and company leaders expect the 2016 Toyota Mirai hydrogen fuel-cell car will take a similar trajectory.
The Mirai could equal the Prius's impact on the industry, Toyota Motor Sales' head of automotive operations Bob Carter told The Detroit News in a recent interview.
That impact likely won't be felt for some time, though.
A major challenge for fuel-cell cars is the lack of fueling infrastructure. There are just a handful of fueling stations currently operating, mostly in California--the only state where the Mirai will be sold for the time being.
Carter said Toyota expects 23 stations to be built by the time the Mirai launches, concentrated in the Los Angeles and San Francisco regions.
Sales of the Mirai--which will be priced starting at $57,500--will also be limited to just 200 units for 2015.
Toyota expects to sell 3,000 Mirais in the U.S. by the end of 2017, at which time sales will have expanded to additional states.
But Toyota is definitely playing the long game.
Carter said fuel cells could become the "dominant technology," but he acknowledged that might not happen for perhaps 20 or 30 years.
Echoing sentiments previously expressed by other Toyota officials, he also described hydrogen as the carmaker's "electrification strategy."
Toyota continues to pitch fuel-cell vehicles and its existing hybrids as more practical than battery-electric cars, because they offer range and refueling time comparable to gasoline cars.
That puts Toyota at the far end of an electrically-driven vehicle spectrum from hydrogen to battery power.
Other makers fall at different points on that spectrum, but given Toyota's impressive track record of persevering with the Prius, other makers may discount its views at their peril.