At the start, there will be drivers that are handing control to the system. So expect self driving cars on the road well before you get a bus without a driver.
The key thing about the interstates are their regularity. Small street roads are much harder. There are more spurious obstacles, including foot traffic, and perception is harder.
Even things like the ease of viewing lane lines matters. This is why solving a sub problem is so essential. If you wait to launch to be able to take on cobblestone streets of old london, a product that only works on interstate 101 and 280 in the bay area is going to launch first. They'll accumulate more data, and they'll win.
The key thing about the interstates are their regularity. Small street roads are much harder. There are more spurious obstacles, including foot traffic, and perception is harder.
Even things like the ease of viewing lane lines matters. This is why solving a sub problem is so essential. If you wait to launch to be able to take on cobblestone streets of old london, a product that only works on interstate 101 and 280 in the bay area is going to launch first. They'll accumulate more data, and they'll win.