If you do the math on the fully loaded cost to purchase, insure, maintain, fuel and park a late model sedan in a major city, relative to how quickly taxi-like usage wears out a car, the Uber drivers are often working for barely above minimum wage.
Their business model (and that of Lyft) relies upon there being a large pool of people who for whatever reason own a rapidly depreciating $25-30,000 asset such as a Toyota Camry, and will consume its lifespan/wear it out to make what looks like a decent hourly wage. But it's not.