Hey CruelBri.. I have been an IVDU it for quite some time now and am definitely experienced I would say, at this point.. and its just one of those accidental things that happens to any one who is an IVDU.. usually not because of the angle, I always have it at just the right angle, exact same angle every time, I am not one of those people who sticks a needle in my arm at a 90 degree angle or some stupid ass shit lol.. its just when you push down, just a little bit too hard on the plunger and the needle moves even just the slightest little bit to far and pokes through, with a sharp brand new needle especially which I always use (nowadays at least), which I like to do a lot of the time, because I feel like the faster you push down the faster and harder it hits you whatever you are slamming(kind of an OCD thing of mine, it probably doesn't really make a huge difference, unless you push it way too slow, which does make a difference IME). Mistakes just happen when you IV drugs, shots get missed, veins get punctured, etc... I rarely have this happen anymore, and if I do, its at the very end of the shot most of the time as I am just about to hit the 10 mark on my 1ml syringe.. like usually I shoot subutex, 80 units of water over 2mg of tex, so I might miss 5-10 units sometimes, but not often.. I use more water than less for that reason! if I even miss just a little bit, then that is less product being wasted, with more water to work with. Also it does sometimes, again, but not often happen when I first register, and think I am in vein, but really I am just barely through the vein, past the underside of the vein, and immediately I will notice, and of course pull the rig out, missing maybe 2-5 units.. then find another veins and re-register until I am where I wanna be.