Entropy man. You think that a whole bunch of neatly aligned atoms would stay that way over time?

Eventually, sure, but I have crappy old fridge magnets that are still going strong after 30 years. What's different about little neodymium rods that they fail in 5?

I think it has more to do with that your body builds up scar tissue around the magnet that makes its wiggles inside your body less palpable, than that the magnet itself weakens.

No.

She couldn't attract metal objects with the magnet anymore.

"Bottle caps refused to leave the ground, and finally, stopped responding altogether."