One of the reasons it took off so fast in San Francisco is because of an incredibly change-resistant, blockheaded bunch of taxi-cab companies that fought every increase in the number of taxi licenses in the city for decades, even after demand far outstripped the taxi companies' ability to deliver. The cab companies also got incredibly lazy and bad at customer service. There was so much more demand than supply that a taxi driver did not need to excel or even be basically competent to stay busy and get plenty of passengers. After years of taking cabs that reeked of cigarettes (and other things), having cabbies talk on the phone, text, and otherwise not pay attention to what they're doing, or who relied on their GPS devices more than their knowledge of the city's streets, customers were delighted to have an alternative. And when the cab companies just crossed their arms and stamped their feet and refused to evolve, they were rolled over by the social media/technology wave. I don't know how it rolled out in other cities, but in San Francisco, Uber's rise was greatly enhanced by the utterly dinosaur-like behavior of the taxi companies.