Tl;dr pre orders are important for developers since they need to meet a quota for publishers, a decrease in pre orders is noticed and something to fear. But let me talk down to you, pre orders mean everything to a company, how many pre order they get when announced helps them calculate their profit. Now, let's say 1.5 million pre ordered. That's a good number for a game that has no gameplay trailer, people just blind bought a game based on the original. It's livestream day, the developers show case what they've been working on. Now this is a very important day, because from my point of view they told us we are leaving are stuff behind because of a new game engine, and most likely a huge rework of weapons and armor, etc. If I see barely a smidgen of change, I'm not pre ordering. Say the 1.5 million dropped to 900,000. That's a lot of money lost, that's a consumer base lost. You have less people investing in your game for the next three years, to a smart company, they pay attention, they notice. If a game reveal is bad developers will know it by a decrease in pre orders, when game reveals should increase because they are buyers who want to see the product before they make a purchase. So if you didn't get the hesitant buyers, and lost a sold person? You're messing up already, that's why pre orders matter, a company knows how much money they'll make by the numbers, and some companies have a quota for games, and I doubt Activision expects no less than a million. Because if they notice the games not doing good currently, they most likely won't give it a chance to improve and just cut the funds. Edit: see Activision/Bungie doesn't care if the game lost players in year 3, they've gotten their money. But not getting their money for a brand new title is something else, they need your money. Money is the most powerful thing in the world, use it wisely.