SUNNYVALE, Calif. — Car enthusiasts, after hearing industry executives discussing the self-driving technology being built into their vehicles, might be forgiven for thinking robotic cars will soon drive themselves out of auto showrooms.

Carlos Ghosn, the chairman and chief executive of the Renault-Nissan Alliance, announced during a news media event on Jan. 7 at the company’s research laboratory in Silicon Valley that Nissan would introduce 10 new autonomous vehicles in the next four years.

Elon Musk, the chief executive of Tesla, upped the ante. In a conference call with reporters last week, he asserted that the so-called Autopilot feature introduced in the Tesla Model S last fall was “probably better than a person right now.”

Mr. Musk also said that within a year or two, it would be technically feasible to summon a Tesla from the opposite side of the country.