Why does appendix carry make people nervous?

I'm looking to start carrying soon and I'm interested in appendix carrying because it's a little more concealable in what I wear but every time I read about appendix carrying people always say that it makes them nervous about having a gun pointed at their junk or femoral artery. I'm definitely not a gun expert by any means but if your gun has an external safety on it and it's on isn't the chance of a ND pretty much zero? Is all this fear because people are trying to appendix carry glocks or other guns with no external safety? If my logic here doesn't make sense please enlighten me but I just fail to see why people are nervous about it unless they are carrying a gun with no external safety. via /r/CCW http://ift.tt/2iHaCBH