Why do we train a martial art?

Anyone can punch/kick/stab/bludgeon another person. Cavemen did it with no training.

So, why do we really train a martial art...in a civilized country...where there are cops, where you can drive away, where you can choose not to fight?

In any ambush encounters, even a trained person is gonna likely get killed. You can't train to defend against a well-done ambush (you just try not to be there).

IMO, we train martial arts:
1. To learn a coordinated, well-constructed method of self-defense that will help keep us out of fights (it's much easier to evade or quickly end a fight and escape if you are trained).
2. As a hobby. Let's face it - the people that scare us are not going to care if we can throw a kick or a punch.
3. For the artistic and historic value.
4. For the athletic and 'toughening' aspects.

People still ask 'why do you talk about sport fighting? I can grab someone's balls, grab someone's throat, poke out an eye with little or no training'. Well, for one thing systematic defense should be performance based. You can't train performance using a collection of tricks you can't practice, a collection of 'deadly moves' you have to memorize and hope you can pull out of your hat in a pinch. The best way to learn performance-based fighting is in a sport fighting environment against similarly-skilled opponents or better yet, higher-skilled opponents.

But let's talk 'venues of fighting'. There are several. Melee fighting, war, one-on-one street fighting square-offs, bar fights (standing start). In a bar fight the fastest, meanest, toughest (luckiest) person usually wins. You can train attributes (speed, accuracy, ability to take a punch, size, strength, etc.).

In melee fighting, often the direct, down the pipe pure aggressive attack wins. You don't use subtle off-angling moves.

In square-off street fighting, actual performance-based martial arts training (or combat sports training) is going to best prepare you. You don't get the chance to walk up and poke out an eye, things are moving around.

So, what's the best way to train? There really is none. Stay out of fights, consider your martial art as a hobby and have fun. To think you'll ever use it and win a bunch of fights is silly and unrealistic, iMO.

Thoughts?

I'm on a FMA forum and the guy says 'why do you talk about sports-fighting? I just grab guys by the throat' 

I thought the guy was taking a martial art so that he could terrorize his wimpy friends. Much of the time they are college dudes who want to be able to have secret cool stuff they could beat up thugs while not really being a fighter and who couldn't get accepted into a team sport because they weren't particularly athletic.

It is a complete waste of time in the sense of really being an effective way to train, or an effective way to defend yourself. It's neither. To train in MA we need to do other stuff, run, lift, and the actual time needed to punch and kick isn't that important. In FMA after the Dog Brothers we realized the key was to have a couple really powerful strikes and a roof block to enter and some penetration footwork, not all this flippy-dippy trapping and disarming.

So, yeah, if you're an amateur, and you're not having fun, if it's not a hobby you're deluding yourself.

People train in MA for different reasons depending on their needs.
I see three main intents in training for MA. None are "wrong." There is overlap.
1 - self defense - to be safe
2 - Martial Way - using MA as a vehicle to develop the self in some way;health, looks cool, status(look I'm a BB), etc
3 - Martial sport - competition

The way you train should depend on what your intent is. That is;if you are training for self defense and learning a slow tai chi form you aren't training for your intent.
The ability to use your MA vs a real attack raly depends more on the training method. Most schools of tai chi do slow forms, etc...not applicable to a heavy attack.
In frequently you have some tai chi schools that teach the throws, chin na, and strikes in combative ways.