When building a video game, it isn't really until the final few months that things come together. As the programming nears its final state, artists begin adding detail to the game world, and designers look to polish things before gamers scrutinize it for every little flaw.
Because of this, early development games look nothing like their final version. It makes announcing a game rather challenging, which explains why we see so many CGI trailers that give you no idea of what the game will look like at release.
We were reminded of this once again during this last weekend when Overwatch's development team at Blizzard showed what the game looked like leading up to release. We're not even talking a few months before, but instead as far back as 2013, back when the walls didn't even have textures yet, and you couldn't even see weapons in your hands.
It looked a little something like this:
Overwatch has come a long way since then, and as of last month has reached 35 million total players worldwide.