Having lived in Japan for 3 years and experiencing a lot of their culture, I've learned that the reason anime characters yell their attacks is because it promotes a fair, honest fight. Japanese people love friendly rivalries, and the only way to truly prove yourself better than your opponent is to give them every advantage and still come out victorious. Only a truly bad person would try to sneak in for an attack and catch their opponent unprepared. And that won't settle any rivalry, even if they won the fight.

Plus, yelling your attacks just sounds cool.

Pokemon world in shambles

My thought is that it helps the audience know what exactly they're doing. Not saying it's necessary because I think a good visual indication will let the audience know, but I think that's what they were maybe going for.

It does in Jujutsu Kaisen... sorta.

Jujutsu kaisen lol

PUNCH IN THE FACE!!!!

Go Go Gadget Anime attack

Except in some power systems where it does.

My kiai says otherwise!

Try telling that to a tennis player

Thunder breathing, first form

I'd have lost 90% of my hype if it wasn't announced

Hard disagree

Spells may require one of three components.

1. an item that is destroyed in the process of casting.
2. a verbal utterance,
3. a physica movement

Meanwhile Saitama whispers...

Also Tennis Players

I always just assumed they're like magical spells and shouting the name is a requirement to cast them

Also, getting more emotional = more power

JIU JITSU!!!

cries in verbal spellcasting components

my favourite take on this is to have characters fighting in groups, then it becomes obviously necessary to call out moves so others know what's going to happen and can know to not stand on the other side of the enemy that's about to be showered in flame.

it also makes a nice contrast between solo fighters and those who simply don't care about collateral damage: some villains can be pure chaos, you can have rogue heroes who just end up hurting innocent people because they don't coordinate, and villains who do coordinate will look way more threatening because they aren't hurting themselves.

If you call out the name of your attack, you better hope your opponent doesn't know what it is, cuz it seems pretty easy to block or dodge something you know is coming.

https://youtu.be/qXpWv-nyHvI?feature=shared

Captain Falcon in shambles.

Pocket sand!

Gamu Gamu covers ears.

Tell that to Austin Powers. Judo chop!

name your attack {{{{ so the enemy doesn't know whats coming

Oh, it does! Tried it, once, very drunk, many years ago (many!), screamed something like "in your face" (actually German: "in die Fresse") and he was out cold. Only medium knuckle pain, I'm not a fighter, so I thought it did something. Don't worry, he earned it, believe you me.