Partial Source: Pwinsider
At this time, there are many people backstage confused over the recent booking of Antonio Cesaro. After his strong initial push and winning the US Title, the feeling is that for one reason or another his stock has dropped. The proof of this was his omission from the WrestleMania 29 card.
Nobody seems to know why things have changed so rapidly for Cesaro, but many feel that this is an example of WWE creative not having a clear vision for many of their Superstars. Vince McMahon also soured on him in recent months but there is no word on exactly why as of this writing.