How come when I shave it doesn't get rid of all the hair?

if u shave and then you get cold, you get the gust bumps so all the hair that was in side gets out a little bit more...or when ur skin rubs on some kind of fabric it pops out a little more like over night because the covers were rubbing against you all night.. so that's why is better waxing or that cream that removes your hair for a month...