Look what happens when Apple DOESN'T even announce their plans. They get followed solely on rumors. Forget about the fact that Apple's product designs get routinely copied, even their strategic movements get imitated.
So if Apple opened up any sooner, that just gives the competitors that much more lead time to create their "answer" to a new Apple product.
And don't give me this nonsense about "Apple didn't invent wearables, they weren't the first, blah blah." Obviously. The point is, if iWatch rumors weren't at a fever pitch, do you really think we'd see so many companies desperate to release a smartwatch? Doubtful. It was just like tablets back in 2010. No companies gave a damn about tablets for at least 5 years, then all of a sudden it was the category everyone jumped right into based solely on "iSlate" rumors reaching fever pitch. For crying out loud, HP even named a product "Slate" because Apples tablet was rumored to be called iSlate.