Musk, who also runs SpaceX and a number of other companies, has been known to make big often exaggerated promises. For example, he once called the Hyperloop, which was never built, the "fifth mode of transport" and famously promised to take Tesla private in a Twitter post, saying he had secured financing that he didn't have.

While Tesla's sales in markets such as Belgium, Netherlands, and Sweden rose last year, the overall picture in Europe is less than rosy for the automaker — esp