Marissa Mayer, Google’s vice president for search products and user experience, has revealed an interesting experiment carried out by the search engine a few years ago.

The goal of the experiment was to determine the ideal number of results to display in response to a search query. Google surveyed its users, who decided 30 results on a page would be best, rather than 10 or 20.

However, displaying 30 search results takes a little longer to load, and Google found that the more search results it displayed on a page, the fewer searches were carried out.

Returning to 10 results per page instead, and speeding up the process by half a second made all the difference.

The same strategy worked for Google Maps too, when the home page was shrunk to 70K from 100K, traffic increased by 10% in the first week.

Mayer believes that the same principle is behind the phenomenal success of YouTube, because users who post videos are able to see them on the site immediately, as opposed to the 2 to 4 day waits for Google Video users.

Slow loading home pages can be a killer for e-commerce sites, as customers tend to turn to a competitor if a site doesn’t load within around three seconds. That’s according to a study that reveals $1.1 to $1.3 billion is lost every year due to slow loading sites.

Further Reading:
Google launches custom search tool for sites