How about two years of his form being poor then (6 league goals in ~50 appearances for Chelsea)? Including the fact he's been playing through injuries part of the time. And his huge salary among the top few in the world.
I see this is the player that Romeo was talking about then, as expected with Nick frantically posting about him.
Will Juventus give him the space to run into, which made him so effective for Liverpool? Suppose that could work with Pirlo teeing him up, but often we've had opposition sitting deep against us.
Edit: Just seen your other post, 30m for a player in great form I would accept. 30m for a gamble on someone looking so distant from his former self, I would not.