Let's talk briefly about what game development looks like.
Prototype:
This is an image of Horizon Zero Dawn's prototype phase. Looks pretty different, huh? At this point they are just testing things to see what works, what feels good, getting a better idea of how they want the game to feel to play. The "game" is probably little more than a small demo area to run around and mess with stuff.
Pre-Alpha:
Here's Control in pre-alpha. It's rough. It's coming together though. Assets are still missing, designs aren't final, it looks and runs like ass. The game is overwhelmingly unlikely to be considered "playable" at this point. Of course you can control the character and do stuff, but many triggers, quests, objectives, etc probably don't really function at this point yet.
Alpha:
Now we're really cooking. Alpha is when a lot of systems and elements start to come together and the developers are pushing for a complete product. Some assets are in, many placeholders are still in use, but the game should be playable to some extent. You might be able to play one or two levels. You're still going to find areas that lack collision, you're going to fall through the world, or suddenly get launched four hundred feet in the air when you get attacked. Think Skyrim. At some point during Alpha is generally when a company will release a game to their internal QA team for testing and bug hunting/reporting. Each build of the game will have many iterations, Alpha 1, 2, 3, and depending on the game or developer, you might move through these pretty fast. It might only be a day or two between versions as massive game crippling bugs get ironed out and features implemented.
Beta:
Here's a beta screenshot of GoW2018. Beta is a tough one, because the word means different things to a lot of different people. Typically, a beta is when the game is considered "feature complete," and can be played start to finish. In Dad & Boy of War's case, a lot of things can still change and improve during this period. Entire models might change or details added to characters and environments where there weren't any previously. This is the stage where everything really cooks and becomes pretty. Beta is when QA testers will push the limits of the game, doing all sorts of weird shit to try to break it. They'll open and close menus as fast as they can, mash every button on every screen, run and jump endlessly into every seam and piece of geometry they can find to try and fall through the world. At this point, the game should be fully playable from beginning to end; generally all quest triggers and flags should work, the game has minimal crashing, and should operate as expected. Many graphical bugs and oddities will persist during early betas, for which there are many. A game will typically be in a "beta" phase for several weeks to several months, before entering the final phase
Release Candidate. After the poor QA team has hammered this game as hard as they could and reported every minor nitpicky spelling error, geometry seam, game crash, freeze, stutter, unusual character traits like a character having
hilariously large hands... The game finally moves to RC1, then 2, 3, and so on. These RC builds will be pushed hard, and everyone on the development team is trying to break the game any way they can so that it holds up in the hands of players. After a period where no major bugs are being found the game can finally, jesus, finally...
Going Gold: The approved RC build of the game is submitted and considered "good enough," to ship to be pressed and sealed up in boxes and put on shelves. At this point, the developers will go home and binge drink and try to forget all about those horribly large hands, god, those hands haunt them so. The following Monday, the team will get started on any day one patches or upcoming fixes that have been found
since going gold and that build being shipped off. If a devastatingly critical bug
is found during this time, the whole process is halted and a new RC will have to be submitted and approved for printing. This is expensive and time consuming and no developer, or publisher, wants to have to go through it.
And that's basically active game development in a nutshell.