because they got training that was only good for inside the dojo. most of them are like that. just because the instructor tells them they are awesome. and because they have belts or trophies they believe they can be invincible.
but unless people are trained for fighting outside the dojo they will all get wasted.
Dojo arts that involve fine motor skill are easily beaten through adrenaline flooding the blood and shutting down their finesse. the violence of real fighting is worse than any tournament match. rules create a safety net, no rules causes the adrenaline to be full on and then cognitive ability is distorted.
experience can be the only help for these people.
or correct training and mental applications.
I gave up on kata dancing and tournaments because they are dojo valid, not street.
no shame for those of you that enjoy it, but you need to get real on your deal folks. unless you have had a few fights that were out of your control and won, you dont know what you can do. if you believe you can stay invincible in life when you have never been tested outside of your dojo then you are a fool. the question asked is very valid. and the reasons listed above are only some of the aspects that cause the fall of many aspiring martial artists.
...and some arts are better than others. even though people make or break the arts some are better at preparing you for fighting outside of teh dojo. if you have never fought in your work clothes, in boots, etc, then you are not even prepared for the restrictions of your daily clothes.
open your eyes, or stay blind and fall.