Genetics.
Much like other body parts they can vary greatly from person to person. As others mentioned it is all about genetics. Though there are some aliments that can cause shrinking or extra growth.
All of them don't. They vary just like penis size.
No.
It stems from the idea that men are supposed to be courageous and brave. The balls or "testicles" are a symbol of manhood. So if you have "big balls", it's a metaphor of taking chances and being daring, as men were intended to be.
as big as my balls balls balls balls
The men faced getting the balls chopped off and fed to there children.
balls
big juicy balls
Men like their testicals,or as some refer to them as 'balls','nuts',or'junk'('Junk maybe what big butts are reffered to')to be touched because it feels good & their soft.Also,they may be not-so-soft at some times. well this is akward
Some Men do and some don't
big balls
yours big
my balls
it means you have big balls+ it means you have big balls+