Tesla succeeded because it focused on the luxury market first by building the Roadster (and then later the model S). It succeeded because they showed that electric cars can be cool and not associated with lame-looking and performing Priuses and Leafs. It succeeded because people bought billions of laptops and cell phones powered by lithium ion batteries, which finally produced the economies of scale and had the right properties that made electric vehicles viable in the first place. Subsidies came later, and Tesla would have done fine without subsidies. Its the trad automakers that are attempting electrics that need the subsidies.