Swedish carmaker Volvo AB has become the first traditional car company to go all out on electric. It has announced that from 2019, all its models will have electric motors. It’s a bold move—and it makes the company the proverbial canary in the mine.

The global market for pure-electric cars is less than 1% of total sales, after all. Volvo might just find that it has gone too far, too soon. If that turns out to be the case, then, taken in conjunction with Tesla Inc.’s sky-high valuation despite its relatively paltry sales, it will point to the existence of something of an electric car bubble.

On the other hand, electric car sales are growing rapidly. This is not merely a developed world phenomenon. China saw more than twice as many sales as Europe last year. And here in India, the government is making a determined push for electric vehicles as well. A successful Volvo post-2019 could embolden other traditional car makers to increase their focus on the segment. That would be for the good. For electric cars to make a dent in the market, premium offerings like those of Volvo and Tesla will not be enough.