I've got a bad habit of using dull needles. I have a pharmacy at the corner of my street, and when I have money I don't even think about buying points. I've got to SERIOUSLY make a serious stride in making this an important thing. Once I had a needle break off into my arm because it was so dull, and when I pulled back.. my hand and the sharp must of twisted, causing it to snap.
I usually ALWAYS rotate my shooting spots. It's hard, because you know that pretty thick vein will hit everytime. Believe me, after a while.. there will be so much scar tissue wrapped around that spot that it'll make a cracking sound when trying to hit it again. Or just plain collapse.
I received Hep C through a used needle, and I don't even know when exactly I got it. Please, everyone, no matter how many times you may bleach, clean, soak the sharp.. don't re-use.