"Watch that first step! It's a doozy!"
As in it's a pretty big one. One with a lot of substance to it. Term based on the old Duesenberg cars that hit their heyday in the 1930's and affectionately coined the phrase, "It's a doozy!" as a way to say, "Now here's a REAL car!"
Because of Stagefright and so on, Google's been forced to pay a lot of attention to security with Android N: particularly the ability to patch core functions of the OS that normally get obfuscated by carriers. In order to avoid getting investigated by governments for still letting hopelessly-vulnerable-and-unpatchable devices be approved, they need to slam that door hard. That's why you have things like seamless updates, which means updates don't take forever to install, and why IINM he core framework is being separated from the user interface (which is what the manufacturers and carriers want to control).
I still haven't heard any call for requiring the use of root-proof tech like ARM TrustZones and Secure Elements; this may have to do with catering to low-end device makers, though.