Hi whoever can answer this

I am not asking for a release date.

Curious as to what is involved with Beta testing, How many people test the game. After errors are fixed then how many play it to make sure it is playing with out errors, how many times or how long. (50 people need to play it without an error before it is released or is it hundreds or do the same people replay it trying to do things differently to see how it reacts.

Thanks