https://www.cnet.com/news/uber-self-driving-cars-reportedly-lag-behind-competitors/

When self-driving car companies test their cars on the open road they measure the vehicles' success and improvement on a number of factors. One such test is how many miles the car can drive autonomously without human intervention.

Uber's driverless cars require human intervention once every 13 miles, according to company documents obtained by The New York Times. This isn't a great rate, compared with Uber's competitors.