How games/movies companies make sure each dvd copy will work?

Question by Cherryhokl Sadasd: How games/movies companies make sure each dvd copy will work?
When a game, or a movies released, there is probably 1+ million copies of it, im pretty sure that the companies not checking every one of them, yet all of them ALWAYS working.
So how can they make sure?

I was laways intrested to know that.
Which disk are they using?
How they are making the copies?

Im really curious to read about it…

Thanks !

Best answer:

Answer by J M
They don’t use a disc they are all first generation copies from computer memory.

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