Why are punches to the head prohibited in some Eastern striking martial arts?

Question

Some eastern martial arts (such as karate, taekwondo) prohibit straight boxing-style strikes/punches to the head in their sports rules:

A punch that makes strong contact with the opponent's hogu scores 1 point. The punch must be a straight punch with arm extended; jabs, hooks, uppercuts, etc. are permitted but do not score. Punches to the head are not allowed.

• https://en.wikipedia.org/wiki/Taekwondo#World_Taekwondo_(WT)_Competition

Punches to the face, groin, and joint are prohibited but all bare-knuckle and elbow strikes to the body and limbs (with the exception of joints), and kicks (including kicks with the knee) against legs, arms, body, head and face are permitted, as are sweeps.

• https://en.wikipedia.org/wiki/Full_contact_karate#Different_formats

But why, historically? With respect to these arts, it seems somewhat impractical - these arts have large amount of possible moves, why are such punches prohibited?

My question is absolutely not an attempt to belittle eastern martial arts, but mainly, to ask why. A lack of these strikes influences style and moves - you cannot (in general) afford such a degree of complex kicks in kickboxing (or muai-thai, for example) - you sometimes just don't have time for it - as your opponent is coming close, within knee/fist striking distance.

Answer 1

As per what was mentioned in the comments, these are competition rules. But these arts do teach and practice face punches/strikes in their syllabus.

I'd like to draw an example from my style: Kyokushin karate. It did have a category for bare knuckle face punches for awhile, but it was messy, it was bloody, and because the head (especially the face area) can be punched easily fighters only focused on the face and disregarded all other less damaging techniques like body shots and kicks. This turned into a boxing match with fighters wearing karate gis.

It made competition uninteresting and dangerous and participation was lacking after the first 2 years. As for Taekwondo, they will never allow head punches with fists for safety reasons, as it is an Olympic requirement.

Answer 2

The reason for the no-punch-to-the-head is to encourage the kicking aspect of the style.

Punches are easier, kicks are far more difficult. Therefore, to encourage use of kicks, there are more point options with kicks: standing kicks, turning kicks, and standing and turning kicks to the head garner more and more points.

Taekwondo needs to ensure that it is distinct from other sports in the Olympics, as well. To ensure a stronger delineation between it and boxing, punches to the head are eliminated. Now that Karate is coming to the Olympics, they, too have the burden of creating a ruleset which distinguishes itself from wrestling, boxing, and taekwondo.

It should also be noted that while official WT-sanctioned events will formally use no-head-punch rules, local competitions that are not WT-sanctioned (eg, open tournaments) can (and often do) allow head punches.

So bottom line, head-punching is disallowed to encourage more dynamic movement with high kicks, and to distance itself from other sports (karate, kickboxing, boxing, etc). While you may be asking about head-punches, you could just as easily have asked about grappling, too. It's for the same reason: to encourage use of kicks in competition. Grappling is a part of taekwondo as evidenced by examination of your poomsae/hyung. But only in the Olympics is this generally enforced: local competitions are free to establish whatever rules they want.

Answer 3

Because of CTE. I would not want my kid boxing, or any other full contact, continuous impacts to the head.