Diplomacy with a gun

After work I watched a TV show for a little while with my son.  The show we watched does not matter because you have seen the scene that I am about to describe.  The bad guy got the drop on the good guys yet somehow the good guy got his weapon pointed at the bad guy without getting shot.  This happens all the time in movies and  TV shows.  As you know the next thing that happens is they start talking.  Then the bad guy makes some threat which causes the good guy to drop his weapon and try to talk the bad guy out of whatever it is that he is planning.

My question is "Why?"  The fact that both parties have weapons pointed at the other is proof that diplomacy has failed.  If you could have solved the problem with talking you would have well before you got here.  The only redeeming quality that I can find in this is the hope that if I am ever in this kind of situation the bad guys (yes, I'm a good guy, if you don't believe me just ask me) will think that these rules are in play giving me a chance to get off the first three rounds.  However, I don't really think that this would be the case since bad guys by definition do not play by the rules.

Other things that don't work in real life are:

• Good guys do not have a force field around them.  This makes walking around in an active gun battle problematic.
• As a rule at least some of the bad guys can shoot as well as the good guys.  Having the good guy hit fifty targets while all of those are shooting back and missing does not make sense.
• Grenades do not make fireballs. 
• Hand to hand combat is a last resort.  You want to start with air to ground weapons(bombs,ICBM, etc.).  Then move to artillery fire, mortar fire/sniper weapons, heavy machine guns/ small arms, hand guns, bayonet, sticks, knives, and big rocks before you go with hand to hand.
• No one is getting up three seconds after being thrown through a window without a cut.
• Operating the action on an M-203 grenade launcher does not load a round.  It is a breech loaded weapon.

There are others, but these are some of the most obvious.