Why do people always say......
"If I ever have to pull my gun, I'm going to use it"??
First, people don't always say this, but many do. Missing from the quote is context. By "use it," do they mean that it will be used at least as a show of force/power, or do they mean they will be shooting it?
Of the folks I have heard say this, they meant discharging the gun.
The sentiment expressed in the quote seems to represent a sense of false bravado (the ninja feelings thing FrankDrebin mentioned). It also seems to represent something of situational ignorance. Obviously, guns do not need to be discharged in all cases where they are drawn.
XavierBreath said he goes by that plan so as to teach himself to be able to administer shots without hesitation. This is a pretty good consideration as you don't want to hesitate at a time when time is critical and winning or losing separated by fractions of seconds. As noted, drawing should not be taken lightly. He mentioned that whether or not the gun is fired, it is a use of lethal force. Technically, that is not correct. Drawing a gun only signifies a threat of lethal force. Lethal force does not occur until the force is actually applied. Lethal force s defined as
We also hold that in this circuit “deadly force” has the same meaning as it does in the other circuits that have defined the term, a definition that finds its origin in the Model Penal Code. We define deadly force as force that creates a substantial risk of causing death or serious bodily injury.
Drawing alone simply does not constitute lethal force and drawing does not create a substanital risk of causing death or severe bodily injury.
If drawing did consitute use of lethal force, then depending on circumstances, you could be put on trial for attempted murder. Since it is not lethal force to draw a gun, then you won't be charged with a lethal force crime for simply drawing the gun.