Bad egg

[Bcoz18]

I just recently got rid of 8 cartons of eggs no issues and started collecting again. I've had these eggs maybe 2 weeks in egg cartons I have about 5 cartons. I started noticing a smell from one egg so decided to open it up and it was black and oh lord rotten. How can this egg be rotten at only 2 weeks old?

 

[NatJ]

How can this egg be rotten at only 2 weeks old?

Could it be an old egg that was hidden in a corner, so it was already "old" when you collected it?

Did the egg have any cracks in it? Cracks can let bacteria into the egg, where of course they are happy to grow. Bacteria can get into eggs through the shell too, especially if the egg was laid on the ground or had poop on it, but even without that.

Do you store the eggs in the refrigerator or at room temperature? Bacteria grow faster at warmer temperatures.

Having a rotten egg that soon is definitely unusual, but I think not impossible.