Nexus 4 Downgrade from 4.4.2 to 4.3 Risks

So I bought my Nexus 4 last month expecting that it'll have a 4.3 OS version. However, my sister accidentally updated the version. Now, I would like to downgrade my OS version. Following this guide: http://www.cultofandroid.com/46632/downgrade-nexus-4-to-android-4-3-jelly-bean-from-kitkat/2/ what might be the possible failing scenarios and what am I going to do if that happens.