ever used a shot timer?
Do you have a clue how long it takes to do this or that, with that or this gun and load, at such and such a range? Knowing such things helps determine what tactics have the best odds of success, instead of just blundering around and counting upon luck.
why do guys just imagine that they will be able to "place" a shot where they want it, while they are being shot at? why imagine that enemies will only have handguns, at 15-50 yds, instead of 12ga of buckshot, or .22 autoloading rifles? :-) Do you know it only takes 1-1.5 seconds to raise a longarm and probably hit you at 25 yds. ? And you think it makes sense to just stand there in the open, with a handgun, for 6-10 seconds, shooting at multiple enemies at 25 yds. What makes you think that you can shoot as well without hearing protection as you can when your muffs are in place? you can easily prove to yoruself that you sure as hell CANNOT do so. :-)
now try it with somebody firing a gun over your head, in the dark, with gloves on, to simulate what combat adrenalin does your your fine motor control.