Depends on the game but absolutely we run thousand iterations of a game, but for balance. Which mechanics keep player engaged you need to get feedback from players
art, design, testing, producer stuff, composer, sound designer writer. Then product and creative manager, art and technical director and thet all the rest. And at the end game can be no fun at all.
Also gta has thousands bugs still, cant imagine how many AI would make and if you could solve to actually complete massive project like that
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