OK, maybe that's a bit facetious... but the Orb is a little expensive at $60, it is under-supplied (heck, it's not officially available at all in the UK) and, as with pretty much any surface, the Nexus 4 does have a habit of falling off it for no apparently reason.
Thankfully (?), an enterprising Etsy seller with a 3D printer has the solution... for another $24. The Nexus 4 Charging Orb Cradle is 3D printed to order in a variety of colours and is specifically designed to hold your Nexus 4 in place and prevent it from slipping. The design file is available to download from Thingiverse if you happen to have access to a 3D printer of your own.
It kinda ruins the aesthetics a bit though...
Click here to view the item