The Case Against Root: Why Android Devices Don’t Come Rooted
 

We’ve written about rooting your Android smartphones and tablets before, but why don’t they come rooted? Google argues that rooting is a mistake for security reasons, as it subverts Android’s security model.

Over the years, Google has added more and more formerly root-only features to Android – from screenshots to support for encryption and VPNs. The goal is to minimize the need for rooting.

http://www.howtogeek.com/132115/the-...t-come-rooted/