Super Pumped: The Battle for Uber by Mike Isaac:
In theory, regulators were against Lyft’s antics; after all, the company was breaking rules. Uber had been recruiting drivers for some time, but within limits; all of Uber’s drivers were licensed livery vehicle operators registered with local transportation offices. Lyft turned that on its head. The mustachioed startup invited anyone with a car and an ordinary Class C driver’s license to start driving for Lyft.
But as one Uber employee competing with Lyft at the time said, “The law isn’t what is written. It’s what is enforced.” To Kalanick’s dismay, SF transit authorities weren’t enforcing a damn thing. For all his bluster about ignoring regulators and disrupting an industry, Kalanick hadn’t actually gone as far as Lyft and Sidecar. Up until then he hadn’t been willing to cross the line into extreme ride-sharing.