The classic golf cart, above, if modified with some features of a traditional sedan, could be a bigger threat to the car industry than Tesla. (April Greer for The Washington Post)

Tesla is dealing with some very lofty expectations. Its sky-high stock price is proof of the meteoric growth investors expect from the electric car maker.

Tesla appears to be up to the challenge. Consumer Reports named its Model S the best overall vehicle for two straight years. Tesla plans to eventually release a vehicle in the $35,000 price range, which will broaden the number of traditional car makers it competes with. To many, that’s when Tesla will upend the auto industry. (Currently its sales are dwarfed by the traditional automakers.)

But researchers at Harvard Business School aren’t convinced that Tesla will be disrupting the auto industry. They laid out their findings in the May issue of the Harvard Business Review.

Their work was commissioned by Clay Christensen, author of “The Innovator’s Dilemma.” In the legendary book, Christensen lays out how disruptive technologies start as cheap offerings that aren’t taken seriously, but then steadily improve and soon take business from the established heavyweights.

Tesla has taken an inverse tack, what’s sometimes called “disruption from above.” A Tesla with the best features costs over $100,000. It’s working to move down the market with more affordable vehicles.

Research fellow Tom Bartman says his team believes Tesla could have the brightest future as an arms merchant in the battery space, where it could use its expertise in batteries and drive trains for simplified electric vehicles.

“Working from the bottom up, a la the theory of disruption, is a surer pass to success than starting from the top and sustaining battle with incumbents, and then pursuing a successful series of sustaining innovations into ever lower price points,” Bartman told me.

True disruptors often work on the fringes of traditional markets and are overlooked until it’s too late. So if Tesla isn’t going to disrupt the auto industry, what could?  Bartman points to what’s bubbling up in China, where 200,000 low-speed electric cars were reportedly sold in 2013. (For comparison, Tesla sold 22,477 cars in 2013.)

These low-speed electric vehicles have more in common with golf carts than a traditional car. The feature set is minimalistic, but the low price point — reportedly from $2,000 to $12,000 — creates their appeal.

“Their alternatives are walking, or riding a bicycle or moped, or taking public transit. So to them it’s not a detriment that it can’t go very far or very fast,” Bartman said. “So those people are buying these vehicles in droves because it’s the best option they have.”

The vehicles, which are basically souped-up electric golf carts, also fly under the radar of potential competitors because they aren’t classified as automobiles.

“It’s not being measured on a lot of market share reports,” Bartman said. “It’s not being talked about heavily because these sales are happening in cities in western China that are not Beijing or Shanghai. They don’t have a high profile or a lot of media outlets that are monitoring what is happening.”

Given their limited features, these low-speed vehicles aren’t classified as cars by the Chinese government. So the low-speed vehicles are exempted from the expensive licensing fees to make a car street legal. This is another advantage. Dodging regulations is a classic move of successful innovations.

“If those cars continue to sell at those rates and the technology continues to improve, everyone’s at risk — whether you are a high-end electric car manufacturer or an internal combustion engine manufacturer,” Bartman said.

So while the world is impressed with Tesla’s beautiful designs and powerful motors, the auto industry’s biggest threat may actually be a product that — for now — looks unimpressive to most Westerners.

Bartman compares what’s shaking out today with electric and gas-combustion engines to the early days of when steamships challenged boats with sails.

Early steamships lacked the speed and reliability to replace sailboats on trips across oceans. But steamships could handle shorter-range tasks better than sailboats, such as traveling against the wind or with no wind. This proved useful for canals and inland waterways, so steamships found a niche. Steam engines steadily improved, and eventually supplemented sailboats.

You wouldn’t want to take a golf cart on the highway, but it’s more than enough power for a city-dweller traveling a mile or two for errands or work. And if makers of these bare-bones electric cars reinvest their profits in the product, it will only get better, broadening appeal to more customers.