Originally Posted by
Crispy_Frog
...........I've noticed that my pins seems to have a shelf life. They don't glide so easily after time............
"after time" .... if you are meaning after you have been using them for awhile, that is different than starting with new, never out of the package. Yes, pins are not as sharp or glide as easily after time/use. The point gets damaged from use. Also, the pin can get dirty/damaged with use too. Just the same as how your rotary blade wears out .... or you can take the first cut and damage the blade by slicing against a ruler, for example.
As the others have said, unopened needles and rotary blades should be just fine despite how long you have them on hand, providing they are stored properly.