Pins and needles do rust/corrode over time and the damage is not visible to the naked eye.
Ran over a pin once when I was quite young and my mom dug the tip of the machine needle out of the corner of my eye....I NEVER intentionally sew over a needle! (I'm slightly OCD regarding safety.)
I pick up a new box of decent quality pins every few years and try to keep them separate from older ones, just so I can use for silks, etc.