Long Hair Tourniquet
Long hair can cinch off stretched earlobe piercings. This risk applies to stretched lobe piercings where tunnels are not worn (that is, the lobe hangs open and exposed), although rings that do fully fill the hole don't stop it.
Long hair can become tangled around the flesh loop and tourniquet it off tightly. If there is also a ring weighing down on the area (which can reduce sensation slightly), you may not notice this has happened for some time.
If your ear then becomes irritated, either by the jewelry or simply general health, and swells, this loop of hair can cut off circulation in the area or even cut into the tissue like a wire cutter. This will, of course, weaken the tissue.
If it happens
Remove the hair by cutting it away. DO NOT tear it, as it could easily do more damage to the ear. Then, massage the ear lightly to restore blood circulation to the area. DO NOT re-insert the jewelry immediately or put any pressure on the area until it is back to normal.