The problem there lies that there's almost zero chance that the game you see @ E3 will be the exact same game that gets released 6 months down the line. Sure, y

The problem there lies that there's almost zero chance that the game you see @ E3 will be the exact same game that gets released 6 months down the line. Sure, you could just stop development, but then you're just wasting 6 months you could be spending making the game better. That could mean adding new mechanics or story, but sometimes you decide that a really cool thing just doesn't fit in to the story you're trying to tell, so you cut it and it's a better game for it. I feel like it's a have your cake and eat it too. That not to mention the industry feedback you get that you could be incorporating.