Google holds off on device encryption requirements for a later version of Android, but why?

Google holds off on device encryption requirements for a later version of Android, but why?
Google holds off on device encryption requirements for a later version of Android, but why?
http://phandroid.s3.amazonaws.com/wp-content/uploads/2014/10/Android-5.0-Lollipop-DSC07205-640x412.jpg
Google holds off on device encryption requirements for a later version of Android, but why?

In Google’s efforts to make Android a more secure platform, the company once required that all devices with Android 5.0 Lollipop or higher would have key partitions of the system disk permanently ...
Read More Google holds off on device encryption requirements for a later version of Android, but why?