Autonomous cars are rife with benefits, but a new research study suggests that congestion and cars on the road will get higher, as we seed control to the computers.

More people will be allowed on the road as regulations are relaxed, allowing old, disabled, and youth to drive a car. That will not only lead to more cars on the road, but a reduction of car idleness in parking lots or garages, as everyone in the family can summon the autonomous car.

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Accounting firm KPMG sees this as a potential congestion crisis, which could see miles driven in a year shoot up from 3.1 trillion currently to 8 trillion, if regulations allow people to drive a car without qualifications.

Most experts see three parts to the autonomous vehicle rollout: human-AI interaction in the next two to five years, fully autonomous travel with regulations in the next five to 10 years, and fully autonomous travel for any human in the next 10 to 20 years.

KPMG still sees autonomous vehicles as indispensable

KPMG’s report focuses on the last part, where everyone has an autonomous vehicle (or can order one) and regulations — at least in the United States — are relaxed to the point where teenagers, elderly, and disabled people are allowed to drive unsupervised.

“It will be indispensable to your life,” Gary Silberg, an auto industry expert at KPMG, said. “It will be all sorts of things we can’t even think of today.”

Automotive-as-a-service could be a potential new market for app developers, creating systems on top of the autonomous architecture. Instead of waiting three days for Amazon to deliver a package, you send your car to a fulfillment center to pick it up; don’t need your car for a few hours? Connect it to Uber and make money while at work.

We might even see a day where cars are public transport, the same as trains and buses, ordered on an app whenever you need one. We assume some people will keep a car on hand, just in-case the Uber app (or whatever future autonomous app is around) fails, but for students and people saving money that might be a viable option.