When I put my little "Five Airplanes" thingie together, I started thinking about what really made my particular choices stand out among all the other excellent aircraft I could have picked. Then I came to the conclusion that the same thing that makes these particular human-made tools remarkable is also the thing that makes any great human-made object remarkable, and that's intangibles.
Every once in a while, an engineer or artist manages to create something that is far more than merely the sum of its parts, something that performs far better than the addition of its specifications on a sheet of paper may suggest. Aviation is full of such creations, for example. There's no specific list of features that made the Douglas DC-3 the legend it is, but rather the way those features add up to something above and beyond sterile numbers about performance, cargo capacity, or range. A well-designed piece of machinery has much in common with a good musical symphony—you can dissect them into numbers and notes, but when you hear the thrumming of a DC-3s Cyclone or Twin Wasp engines, or the opening motif of Beethoven's Fifth Symphony, you realize that you're witness to something significant.
Almost every one of us has favorites among our selection of tools, and most of the time, we can't precisely put our finger on the exact reason why we prefer our favorites over any other tool for a particular job. The more vital the task, the more attached we are to the tool in question, and there are few issues more vital and personal than self-defense. Therefore, people tend to get very attached to their choice of sidearm, for example, and that's the main factor behind the endless "brand war" discussions we see on the discussion boards dedicated to guns and self-defense.
A person's preference in personal sidearms is unassailable. You cannot convince a man of the inferiority of his pistol by dragging out sterile data if he's been carrying that pistol through thick and thin, war and peace, calm and danger, for the last ten or twenty or thirty years. Their reason for picking that particular gun might be insufficient for you, and your personal preference may beat theirs on paper when it comes to empirical factors like capacity, weight, or loading speed, but you cannot overcome intangibles with mere numbers.
Take my personal preference as an example. I've often talked about the virtues of my carry gun, the Smith & Wesson K-frame with a three-inch barrel. In a toe-to-toe battle of statistics, any Glock fan could beat me soundly with sheer numbers. A Glock 19, for example, is lighter, holds two and a half times more ammunition, and is much faster to reload than my S&W Model 13. On paper, the Glock 19 is the superior self-defense weapon, beating the Model 13 in nearly every category. So why do I carry the Smith instead of a Glock 19?
Why, intangibles, of course.
The M13 has a heft to it that's lacking in the Glock. It has just the right amount of weight—heavy enough to absorb recoil and make follow-up shots easy, and light enough to not be a burden on the belt. Yeah, the Glock is lighter, but the Smith is light enough, striking just the right balance between shooting and carrying comfort. It doesn't need to weigh twelve ounces, because it's not a pocket gun. (On a side note, if you can tell the difference between a 25-ounce gun and a 30-ounce gun on your belt, you need a better belt and holster, not a lighter gun.) Now, how do you quantify the "proper" weight for a gun? The simple answer is that you can't, because "proper" in this case depends on the purpose of the gun, and the opinion of the person who has to carry it. To me, a three-inch K-frame on the belt is just right, but to someone else, a fifteen-ounce J-frame in the front pocket is just right. Can you argue who's correct, armed with just a spec sheet with numbers on it? Of course you can't.
The M13 has other intangibles that make it superior to the Glock in my mind. It's more reliable—not hugely so, since the Glock is a very reliable design as well—but enough to make me trust it just a smidge more. It's more adaptable to my hand, and balances better because it's less top-heavy. It's easier to verify as loaded—all I have to do is to glance at the back of the cylinder. It's a self-contained system—there are no magazines to lug around, and no need to spend another $200 on a sufficient stash of them. It lets me keep all my brass, every last piece, and I don't have to bend down and spend fifteen minutes picking up empties every time I go to the range. It's less ammunition-sensitive—I don't have to spend any time trying to find a load that feeds well, and I can load and unload it a hundred times a day without having to worry about bullet setback and marred brass or bullets. It holds less rounds than the Glock, but I'm a better shot with it because it makes me place those fewer rounds more judiciously—with the Glock, I always have the thought of "I got plenty more" in the back of my head, and it's easier to get sloppy with shot placement. It's more monolithic in construction—you can't put it out of battery by pushing the muzzle into an assailant, and it makes a better impact weapon in a pinch.
All of these factors put together add up to something that I don't get with any other carry gun, and that's something you can't really express with cold, hard data. The M13 on my belt gives me the warm-and-fuzzies in a way the Glock doesn't, and you will not be able to talk me out of one in exchange for the other by talking about capacity, weight, reloading speed, or anything else to which you can attach numbers.
The next time you read a discussion about Glock vs. 1911, pistol vs. revolver, Ford vs. Chevy, Piper vs. Cessna, New England vs. Dixie, or any other attempt to quantify intangibles and determine that "A is better than B", look at it as if they're trying to establish whether Beethoven's Fifth or Mozart's Symphony No.40 are the better compositions. Could there be a bigger waste of time?