I'd like to know what their criteria for "abandoning" EVs is; is it that twenty percent buy an EV and then sell or return it in favor of owning only gas-powered

I'd like to know what their criteria for "abandoning" EVs is; is it that twenty percent buy an EV and then sell or return it in favor of owning only gas-powered vehicles, or are they also including people who buy an EV and then buy a gas-powered car in addition to the EV they already have? There are a lot of reasons for people to do the latter that don't necessarily mean they're dissatisfied with their EV. The article links to an abstract which is ambiguously worded, and the article is paywalled.