If you have a 'strawberry' pin cushion, the little strawberry has something (I'm not sure what it is) that will sharpen your pins. When I have a stubborn pin, I stab it a couple of time in the little strawberry and lo and behold it works so much better. If that does not work, then into the container(trash) it goes.
I never throw pins or blades in the trash, without them going into a 'safety' container first. I keep a old altoids box next to my sewing machine just for them.