With many automobile manufacturers making the shift to electrifying their entire line up, the industry is betting big on an all-EV future. But a survey of Californians showed that some 18% of EV owners switched back to gas-powered vehicles, while 20% of PHEV owners returned to fossil-fuel-only combustion.

The survey was carried out by Scott Hardman and Gil Tal of the University of California as they decided to examine how local residents perceive electric vehicle ownership. The test was conducted with the participation of 4167 households who completed the survey. However, only 1,842 respondents made a decision as to whether they would keep their EV.

1,458 people responded positively saying they would want to keep their EV or PHEV, of which 1,213 had already moved onto another EV, with 245 buying their EV back after the end of its lease. But 384 EV users reported that they made the move to go back to internal combustion engines.

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The study carried out has already raised eyebrows. One reason that ICE returnees cited was the lack of infrastructure in place to support electric vehicles. Other takeaways from the report, noted by Ars Technica, shows that nearly 70% of those who opted out of electric power didn’t have access to a Level 2 charging plug at home. Other key takeaways are that those of the 20% that moved back to internal combustion engines were more likely to be younger individuals who are starting out in life. These participants typically earned less than the EV remainers, were less likely to live in detached accommodation, less likely to be male, and rented more.

However, it’s not all doom and gloom. The survey was carried out between the years 2012 and 2018. Since then, we’ve seen more commitment to the construction of EV infrastructure. In addition, power companies and manufacturers have begun working harder to increase access and reduce costs of Level 2 home charging.

Notably, Tesla was the brand that retained its customers the most, with just 11% of those surveyed leaving. This may have something to do with Tesla’s charging infrastructure, as well as the maturity of their powertrain tech. If anything, this survey suggests that with a more robust network of charging stations, as well as better EVs on offer, more would be willing to not only make the switch to electric but stay there.