The Authorship markup was first unveiled by Google in June 2011. Its roots can be traced back to the company's Agent Rank patent of 2007. Bill Slawski, an expert on Google's patents, says that the Agent Rank patent is a type of system wherein multiple pieces of content are connected with a digital signature that represents one or more "agents" (authors).
Three years after Google Authorship was launched, the company decided to discontinue the project. The announcement came from John Mueller of Google Webmaster Tools which he posted in Google+. According to Mueller, Google will stop displaying authorship in Google Search. Likewise, it will no longer track data from content with the rel=author markup.
Google noticed that displaying the authorship information wasn't as useful as the company had thought it would be. At some point, it can even distract from the results. For these reasons, Google decided to axe the Authorship project.
Over the past eight months, Google has made two major reductions of Authorship rich snippets. In December 2013, the company reduced the display frequency of author photo snippets. As a result, only a few Authorship results were seen with an attached author photo while the rest had just a byline.
By the end of June 2014, Google has totally removed all author photos from the search results on a global scale. Only bylines for any qualified authorship results remained untouched.
Mueller explained that the photos were removed as part of the company's move in unifying the user experience between searching through the desktop and mobile. Since mobile devices have limited screen space and bandwidth, there is difficulty in displaying author photos. Moreover, Google noted that author photos have no significant effect in the number of clicks that a page gets. In other words, authorship is neither beneficial nor harmful.
"If you're curious - in our tests, removing authorship generally does not seem to reduce traffic to sites. Nor does it increase clicks on ads. We make these kinds of changes to improve our users' experience," says Mueller.
In spite of these changes, Google says that it will continue displaying Google+ posts in the main search results and on the page's right-hand side.
"It's also worth mentioning that Search users will still see Google+ posts from friends and pages when they're relevant to the query - both in the main results, and on the right-hand side. Today's authorship change doesn't impact these social features," adds Mueller.
Google's decision is just one of the several decisions that the company has made based on its commitment in looking at things that work and those that did not even meet their expectations. When a feature doesn't work well enough, Google drops it and moves on to the next one.