People aren't buying Cesc because he has injury after injury. Even in La Liga where the game is not as physical as the EPL.
In the EPL, he will probably spend half the time on the treatment table. And his form hasn't been great. And he hasn't kicked on as a player since his early days at Arsenal. I don't think his overall game has improved at all in Barcelona, and that is why he is being sold in the first place.
Barcelona really do not rate him otherwise they wouldn't be getting rid of him considering Xavi's career is now effectively over.