The key, experts say, is not to dwell on the technology, but to accent the basic benefits for consumers — a lesson GM learned too late.
"Automakers need to educate buyers that owning a PHEV is effortless," Harley said. "There are fewer trips to refuel, which means PHEV ownership frees up time, and operating costs are much lower, so owners will save money."
Compare that bread-and-butter message with one of Chevy's early ads, a 2012 Super Bowl spot, where the Volt was presented as a futuristic vessel that space-traveling extraterrestrials were interested in probing for its "really advanced" technology. The central joke was also a big tell: No matter how many times they had it explained to them, the aliens struggled to understand the concept.
Other early Volt commercials played it straight but featured inconsistent messaging that compared the car to everyday electric appliances and referred to it as an "extended-range electric Volt."
It seems like common sense, but Harley says automakers must remember to "focus on the positives and the seamless ownership experience. Don't make the technology appear alien or complex," even if it is highly sophisticated.
Steve Majoros, director of Chevrolet marketing, cars and crossovers, has acknowledged that GM focused too much on the technical aspects when introducing the Volt rather than the "promise of what Volt delivered," which was a cleaner, more environmentally friendly driving experience.
GM has sold nearly 155,000 Volts since the vehicle's arrival in December 2010 — peaking with the arrival of the second-generation car at nearly 25,000 units in 2016.
Those who understood the technology and purchased the vehicle were overwhelmingly satisfied. Many early adopters became ambassadors for the car and its technologies on Internet forums and social media channels.
GM routinely touted the vehicle as having among the highest customer satisfaction in the industry, and the Volt topped Consumer Reports' annual Owner Satisfaction study in 2011 and 2012.
"The Volt was successful among the people who bought it," said Dan Edmunds, an engineer and director of vehicle testing for Edmunds.
And yet even with several more brands offering plug-in hybrids, including the top luxury makes, sales remain at niche levels, and a knowledge gap remains about where PHEVs stand in the spectrum between gasoline vehicles and full electric ones.
"The problem with PHEVs is it's a mouthful, and people still aren't sure what a PHEV is," Edmunds said. "Nobody's been able to figure out how to talk about a plug-in hybrid, and I think that's because we started on the wrong foot."
Edmunds isn't talking about the Volt. He says the misunderstandings go back to the Toyota Prius and Honda Insight, vehicles that were labeled hybrids even though consumers could operate them just like any other gasoline-powered car.
The term "hybrid" might have been better saved for a vehicle such as the Volt, which involved two powertrains as well as two refueling mechanisms.
At launch, GM resisted calling the Volt any type of hybrid, instead characterizing it as an EV with a "range extender," a term Edmunds says muddied messaging for the car even further, given that battery EVs were rare and poorly understood at the time.