Traffic Jam
What causes bad traffic in the morning?
Not the cars but the collective routine, spatial configuration, driving behavior, change, and adaptation.
Imagine the city in 3D with many levels up, and then the road system with fewer levels or an almost 2D configuration.
The vast population that usually adopt the nine-to-five working lifestyle would gush down to the limited road system in the same period of time to go to work.
An inside of the apartment lifts cramp up before the traffic jam, and the traveling downtime begins to add up when the lift car has to stop on almost every floor to pick someone up.
Whenever there is a change from a bigger space to a smaller one, delay happens due to the need for adaptation for the change.
The same goes for the road system. When a bigger road meets a smaller road and vice-versa, the cars stop and delay begins for their speed change adaptation.
Not only that, human driving behavior that causes a sudden change in their vehicular speed such as the need to hit the brake pedal and halt or slowdown would make a compounding, sequential delay for each car, and subsequently a complete stop for the cars far behind.
I imagine that to make the traffic better is to eliminate car speed changing, halt and stop that needs adaptation as much as possible.
Imagine what The Boring Company is trying to solve but with access to the electric pod to transfer your car that does not begin at the roadside parking but the basement of each apartment.