In five nights at Freddy's 2 the music box is used to keep the marionette in a box.
This feature was added so people do not stay in the Freddy Fazbear mask.
When in the mask you can not access the camera, which is required to wind up the music box.
gaming.stackexchange.com/users/92206/longjacob1
So the marionnette can't get out of the box.
It was added because when you are in Freddy Fazzbears head, you do no have access to the cameras.
gaming.stackexchange.com/users/92397/jordan
The puppet pops out if you don't wind up the music box for a while, but it'll take a while for it to pop out
gaming.stackexchange.com/users/92443/user92443
If you do not wind up the music box the marionette (puppet) will pop out of it, although it may take a while for it to pop out.
It was also made so people do not stay in the Freddy mask all the time because you need to access the music by using the camera
and you cannot use the camera with the mask on because that would not be scary.
gaming.stackexchange.com/users/92693/Crystal James
The purpose of winding the music box is in order for the Puppet animatronic not to kill you.
It starts to unwind as soon as each night starts except for night 1 when it starts unwinding later.
As I stated the Puppet will hunt you down if it unwinds all of the way and once that happens there is no way to put the Puppet back.
This and foxy are the two preventative measures stopping you from just sitting there with the Freddy Mask on.
Also, if you do get the game, take note of when you hear "Pop Goes the Weasel".
This is the tune that plays when the music box unwinds all the way and the Puppet is ready.
gaming.stackexchange.com/users/131145/Beminfire
What happens when you don't wind up the music box in Five Nights at Freddy's 2?  I'm just wondering. I don't have the game yet, so before I get it I would like to know.
What happens when you don't wind up the music box in Five Nights at Freddy's 2?
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<five-nights-at-freddys-2>
gaming.stackexchange.com/questions/191831
gaming.stackexchange.com/users/92292/Dalton
This feature was added so people do not stay in the Freddy Fazbear mask. In Freddy Fazzbears head, you do no have access to the cameras. The purpose of winding the music box is in order for the Puppet animatronic not to kill you. The music box has to be wind up, in order for the player to survive longer.
Explanations regarding the music box.