Why doesnt nail polish dry inside the bottle??

my cuzins and i were painting ours and we wanted to find out why!Why doesnt nail polish dry inside the bottle??
It does dry out if you leave the lid off long enough. When you are using it, you dip the brush in, stirring it so the air is not touching the same polish at the surface for long enough to dry.Why doesnt nail polish dry inside the bottle??
Polish contains solvents that evaporate when you apply it and allows the enamel to dry. The solvents cannot evaporate while sealed in the bottle, at least not for a long, long time.
Cause the air can't get in if the bottle is tight enough.





if you had it out in the open it would dry


and without the cap on





(:
I think because air has ot make the polish dry, and because the bottles are air-tight, it doesn't dry. Thank gooness for air-tight bottles, right? :)
The bottles are air tight. It takes air to harden the nail polish.
Believe me, after a while it does.