For instance, two-and-a-half years ago, Google's auto engineers thought they were basically done with their car efforts. They had added some autonomous tools to the car that they thought would help drivers.
However, when Teller allowed some Google employees to drive the cars home, telling them to make sure they were always engaged with the car, he found that many of them weren't paying attention to their driving at all.
That discovery prompted the GoogleX engineers to get back to work and make a fully autonomous car that required no driver intervention.
"Pretty good most of the time is not good enough for a self-driving car," Teller said. "The cars performed flawlessly. The people did not. People don't pay attention when they're actually supposed to be driving. They're putting on makeup. They're texting... We learned that if you are going to have a self-driving car, it has to go from Point A to Point B with no human intervention."
The GoogleX team also worked on Project Wing, which entailed building an autonomous drone for delivering goods. The team chose to deliver heart defibrillators to people who call 911 to report having a heart attack.
Teller said they figured they could get the potentially life-saving equipment to the person in need much faster.
What they learned, however, was that people generally don't know how to use defibrillators, so the whole project wasn't as helpful as they had hoped it would be.
"They're not easy to use and if you can't use it, it's not as world changing as you'd hoped it would be," Teller said.
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