"YouTube let people see the video right away," Mayer, vice president of search products and user experience, said during a short talk. "That's why it did so well."
By contrast, people posting to Google Video had to wait anywhere from two to four days for the video to be vetted and posted for public consumption, Mayer said.
Google announced that it was acquiring YouTube for $1.65 billion in stock last month.
In a survey on search, Google asked people how many results they would want by default; they responded that more is better, Mayer said. So the company conducted an experiment, providing some searchers with 30 default results. But it took, on average, a half-second longer to get those results than when the default was 10 results, she said. Out of frustration, people conducted fewer searches.
"This indicated extreme unhappiness," Mayer said. "It was clear that we weren't going to make this change."
At one point, Google realized that the Google Maps home page had grown to more than 100 kilobytes. "So we took Google Maps and we put it on a diet, and got it down 20 to 30 percent." Users responded positively to the change, she said.
Internet users want to see results right away or they will leave the Web site, she said. Speed--the ability to interact with software and content, and see immediate results-- is a key aspect of Web 2.0 applications, she said. The popularity of user-created and user-edited online encyclopedia Wikipedia, for example, illustrates that people like to have an "immediate feedback loop," Mayer said.
Work needs to be done in the mobile space, though, according to Mayer. Mobile devices suffer from slow data transfer, and it takes too long to input data and interact with Web applications on the devices, she said.
"Even applications like Google Maps for Mobile, while good, are fundamentally too slow," Mayer said. "You will see improvements to speed that up."