The most important theme for Tesla Motor Inc.’s shareholders isn’t revenue or profits. It’s patience.

Wednesday’s quarterly letter to shareholdersmakes for fascinating reading, as the Palo Alto, Calif.-based company expanded sales and support around the world. Tesla TSLA, -5.06% has installed 23 superchargers in 10 cities in China, the world’s most populous country and second-largest economy. It recently introduced the Model S in Japan and Hong Kong, and will soon do so in Australia. It was a reminder that the company — whose market value is a staggering $30 billion even though it sells only 30-something thousand cars a year — is essentially still a start-up.

Shares of Tesla rose about 6% to $244.80 Thursday, up 54% so far this year. The stock trades for about 8.5 times sales, which is a high valuation, and GAAP profits are nowhere in sight. However, that stock price may seem downright cheap a few years from now.

The company delivered 7,785 Model S cars during the third quarter, which works out to 599 cars a week. Then again, the company said it lost a month of production as it worked to retool its assembly line to produce “more than 2,000 vehicles a week by the end of 2015.”

Tesla said Wednesday it expects production to grow by 50% in each of the next two years and “probably for several years to follow.”

Tesla CEO Elon Musk, during the company’s earnings call Wednesday, said demand was holding up very well, despite contrary speculation in the media, even without advertising. “Demand is not the problem,” he said. “We’re growing our production by 50% year-over-year, as far into the future as we can reasonably project.”

That may seem like a far-fetched growth target, but Musk certainly has the credibility to make it seem like an achievable goal. After all, he has done what so many others could not, including producing a powerful electric car with over 400 horsepower, and leading SpaceX, which has developed its own rockets and spacecraft.

Tesla’s third-quarter sales were up 11% from the second quarter, despite the loss of one month’s production, and sales almost doubled from a year earlier. The company’s gross profit margin, which was already remarkably high for an auto manufacturer, improved to 30% in the third quarter from 28% the previous quarter and 24% a year earlier.

Meanwhile, Tesla continues to improve its flagship product, by introducing a dual-motor, all-wheel-drive system for better traction, as well as a set of autopilot safety features. The company continues to tout its electric car’s performance against gasoline-powered cars. “The Model S P85 already outperforms gasoline-powered cars in the same class with its ability to deliver 100 percent of peak torque from a standing start,” the company said in an Oct. 10 press release. Tesla said its dual-motor system doesn’t have to sacrifice efficiency in order to improve traction.

The company said Wednesday it’s made numerous other improvements to the seats, sun visors, doors, air suspension and other features of the Model S “in response to customer feedback.”

Another innovation is the company’s “Resale Value Guarantee” program, which allows customers financing their Tesla cars through the company to sell them back to Tesla for 50% of the original base price, plus 43% of the original base price for options.

Tesla has begun construction of its Gigafactory for battery production in Nevada, which will help it ramp up production in the years ahead.

A major risk the company will face at some point is competition form larger rivals’ electric cars, which will enjoy much higher production volume. But they haven’t introduced any “Tesla killer” yet.

Tesla plans to expand its product offerings with its new Model X, which promises to “blend the best of an SUV with the benefits of a minivan.” It will be introduced next year.

Is Tesla’s stock highly speculative? Yes. But when is the last time you saw a company selling such a unique, innovative product with so much real-world potential? When considering the combination of an appealing electric car, a seemingly endless stream of innovation, strong demand and the expectation of exponential growth, an investment in Tesla’s stock, within a relatively small speculative portion of a portfolio, looks like a reasonable bet.