What do the majority of the criminals want? They want items that are easy to sell, cash, or credit cards in the easiest manner to obtain with the least likely chance of getting caught, arrested or shot. Does attacking the guy that they can see has a gun fit into that goal? Not at all. Why in the world would your average criminal attack the guy they can see has a gun when they could just wait 5 minutes for that guy to leave, or go down the street one block to the next convenience store? Criminals are more lazy than they are stupid. If they want a gun - first it means they probably don't have one and second - it's a hell of a lot easier just to steal money and buy one, or steal a gun left alone by itself - then it would be to try to take it from the person carrying it.
One study:
http://www.gunfacts.info/pdfs/gun-facts/6.2/gun-facts-6-2-screen.pdf
Printed page 29:
60% of convicted felons admitted that they avoided committing crimes when they knew the victim was armed. 40% of convicted felons admitted that they avoided committing crimes when they thought the victim might be armed.
So, if I have a 20% less chance of being the victim of a crime because they know I am armed, then why would I not take advantage of odds that are in my favor? It's not about absolutes. I am not going to be dumb enough to think the criminal
will not attack me
ever because they see my gun. But common sense would tell you that the criminal is less likely to attack me, vice the 99.5% of the rest of the population that is not visibly carrying a gun.
And, maybe I am an attention whore, but I like the attention I get because of my gun. Every once in a while, probably about 1 or 2 times/month I will have a conversation with someone because they noticed my gun. 95% of these encounters are positive or at a minimum educational. Of the few negative reactions I have encountered - 3 out of 4 of those have been from "concealed carry only snobs" that can't resist telling me that they have a CPL and carry their gun concealed and so should I.
In addition, if I do happen to have to use my gun, it is quicker to draw, with less movement, from open carry than it is from concealed carry.
Also, I can carry a larger caliber, higher capacity gun if I don't have to be concerned about hiding it.