
If you get an OTA (over-the-air) update for your Moto G and it fails, here's what you can do. First, a few requirements:
A Moto G. This may work with the Moto E or X as well. YMMV.
Retail Android. This goes without saying, but you won't get an OTA update unless you're running one of the stock/retail ROMs.
Your phone has been rooted or otherwise customized (custom boot logo, custom recovery, etc). This isn't a strict requirement, but it's probably...