Tesla's June launch of its long-awaited "robotaxi" requires a lot of qualifiers: it was supervised, open only to a few invitees and included somewhere between 10-20 vehicles. The stock jumped 8% the day after the launch, and some participants and observers called it a success. The shares have largely given back that gain since then.

Electric carmaker Tesla launched a limited version of its driverless taxi service in Austin, Texas, this week. Chief executive Elon Musk has touted the "robotaxis" as a potential boon for the company and its customers, eventually offering car owners a way to make money off their vehicles when they aren't using them.