On Thursday May 23, 2019, Engadget wrote:
Google Duplex still isn't completely ready to book your reservations -- a significant percentage of calls are handled by humans.
Google's Duplex reservations might be more widely available, but that doesn't mean the AI is ready to handle every call. The company has confirmed to the New York Times that about 25 percent of the Assistant-based calls start with a human in a call center, while 15 percent require human intervention. In the newspaper's tests, the ratio was higher -- real people completed three out of four of their successful bookings.
There are multiple reasons for relying on the human touch. It pitched the technology as capable of handling all kinds of reservations, but that's not always true.