Goku has never been bright. The mighty hero of Dragon Ball has definitely matured over the years, having grown up and started a family. Unfortunately, his knowledge outside of martial arts is rudimentary at best.

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Dragon Ball Super has been criticized for playing this up. Here, Goku has essentially reverted to the mindset of a three-year-old kid, undermining his development and rubbing many fans the wrong way with his stupidity. That being said, he also has his fair share of dumb moments in Dragon Ball Z. Several points in this long-running series see important plot points simply slip his little mind.

Updated May 16, 2022, by Ritwik Mitra: Goku is one of the most iconic shonan protagonists of all time. His fights are the stuff of legends, with his amazing powerups and fighting spirit helping him to secure victory more often than not. However, he's always shown a penchant for being rather stupid at times, which is mostly played for comedic effect. That being said, there are occasions when his lack of intellect can be fairly frustrating, and these instances are the worst of the bunch.

13 Solar Flare

Goku using a Solar Flare in Dragon Ball Z

The Solar Flare technique is a pretty useful way to distract opponents and get some much-needed breathing room. Goku actually uses this technique sometimes during the early parts of Dragon Ball Z. However, Goku has barely used this technique later down the line in the series.

It's a shame, since there are several moments across the latter half of Dragon Ball Z and Dragon Ball Super where Goku could've used this technique to buy some time for himself. It's possible that the showrunners thought that using this technique was too cowardly for Goku, which is perhaps why he barely uses the Solar Flare nowadays.

12 His Telekinetic Powers

Goku-Dragon-Ball-Super-Super-Hero

Telekineses is a pretty great and nifty power that can allow users to move objects with their mind. It's a skill that Goku has used time and time again, although its use has become more infrequent over time. In fact, there's not a single episode in Dragon Ball Super in which Goku actually used this power to do anything useful.

While it's true that a series about punching people doesn't really need to focus too much on telekinesis, that doesn't mean that it should just be discarded outright. It makes Goku look pretty stupid at times when he could've used this power to make things easier for himself and those around him. Since he's so powerful, he should ideally have such a powerful version of telekinesis that he could do all the household chores without even lifting a finger!

11 Dragon Fist

Goku's Dragon Fist

The Dragon Fist is one of the most flamboyant and amazing attacks in Dragon Ball, and it's rather odd that this technique is only used in the movies. Regardless, it does let Goku finally use his Super Saiyan 3 form to actually defeat an opponent, and that too with a signature attack that is exclusive to this form as well.

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The Dragon Fist needs to come back in Dragon Ball, especially since Goku has whipped out the Super Saiyan 3 form at times during the series. The fact that he didn't use this technique against Beerus genuinely makes it look like he completely forgot about it.

10 Heart Virus Medicine

Goku's Heart Virus in Dragon Ball Z

When Trunks travels back from the future, he reveals that Goku will die of a rare heart virus. Thankfully, the kid brings a batch of medicine that hasn't been invented yet. If Goku takes this, then the virus will be a thing of the past (pun intended).

However, he can't follow these simple instructions. Since he doesn't show any symptoms, Goku doesn't take the medicine. Instead, he just sticks it in a drawer. The virus then acts up during his fight with the androids. Even if he only planned to take the medicine as needed, why didn't he bring it to the battle just in case? He almost deserves to have his energy stolen for this oversight.

9 Flaunting Future Knowledge

Goku, Bulma, and Trunks in Dragon Ball Z

Another warning from the future goes unheard. Trunks wants to keep his identity and warning a secret to everyone but Goku. He explicitly tells him as much, fearful of changing his birth or other events in unexpected ways.

On the day of the androids' arrival, though, Goku conspicuously guesses the name and father of Bulma's new baby. This obviously can't affect Trunks's conception, but who know what else it could change? Look at how radically different the androids are simply due to Future Boy's intervention. Then again, try explaining the butterfly effect to Goku.

8 Arale

Goku and Arale in Dragon Ball

The Saiyan's boyhood adventures eventually led him to Penguin Village. It was here he met Arale, the heroine from Akira Toriyama's previous work, Dr. Slump.

Being a robot from a gag manga, she displayed unbelievable speed and strength, keeping up with Goku on his Nimbus Cloud and making short work of General Blue. It goes further in Dragon Ball Super when she sends even Vegeta flying. A pint-sized powerhouse like her could be an invaluable ally against the countless threats the Z-fighters have faced over the years. Goku's usually good at remembering strong warriors. Once Arale is out of sight, though, she's also out of mind.

7 Keep In Touch

Goku and the gang in the Dragon Ball Z epilogue

Goku may protect his friends with everything he has, but don't expect to see him at parties. He's usually busy training. Fans see how far this goes during the epilogue.

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In the ten years since Kid Buu's defeat, he only visited once. It's not even like he has to plan a trip or schedule a flight. All the hassle of travel is rendered null and void by his Instant Transmission technique. Even if that's too much trouble, would it kill him to pick up a phone?

6 Gohan Doesn't Like Fighting

Goku and Gohan in Dragon Ball Z

On one hand, this demonstrates some impressive observation skills on Goku's part. He notices his son's latent abilities over the years and realizes Gohan has the best chance of beating Cell. He even fights the android antagonist first so that the kid can see his moves.

It all seems well-planned until he remembers that Gohan doesn't even like fighting. To say nothing of the pressure of pinning all his hopes on an eleven-year-old boy, this also represents a crippling lack of communication. Goku should know this crucial detail about his own son. At the very least, he should have discussed his plan with Gohan first before blindsiding him with this pivotal fight. No wonder people say Piccolo was a better dad.

5 Cell Is Part Saiyan

Goku and Cell in Dragon Ball Z

As a warrior race, Saiyans get stronger after every fight. Even if Vegeta never told him about this particular perk, Goku experienced it himself during his many hours of training. It was particularly apparent during his flight to Namek, where he would constantly wear his body down, eat a rejuvenating Senzu Bean, and come back tougher than ever.

Because he's such a sporting guy, Goku gives Cell one of these beans after their battle. This way, the villain has a fair fight with Gohan afterward. What Goku doesn't account for are the Saiyan cells inside the android's body. Coming back from a damaged state would surely make him stronger, too, thus diminishing Gohan's already-slim chance of victory. Once again, Father of the Year.

4 Buu's Head Tentacle

Super Buu in Dragon Ball Z

Bubble gum baddie Majin Buu can absorb other fighters and add their strength to his own. He simply sends a piece of himself out to envelop his target and then reattach it to him. This technique comes in handy when he absorbs Gotenks and Piccolo, allowing him to overpower the formerly superior Gohan.

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When Goku comes to the rescue, he cuts Buu into pieces but fails to notice that part of the monster's head tentacle is missing. It doesn't take a genius to figure he'll try another merger in a moment of desperation. Yet, the hero acts all surprised when Gohan falls victim to this. Luckily, Vegeta shows up with brain cells to spare.

3 Not Accounting For Time On Snake Way

Goku on Snake Way in Dragon Ball Z

In all fairness, this is on both Goku and King Kai. To prepare for the impending Saiyan attack on Earth, the hero trains with the Lord of Worlds. He makes great progress in the following months, but he takes the teaching right up until the day the aliens arrive.

Unfortunately, he fails to account for the time it takes to travel back across Snake Way, transport to Earth, and get to the battlefield. It previously took him six months to clear this distance; he manages to cut it down to a day with his new abilities. Still, Goku's friends might have survived had he timed his training better.

2 Not Bringing King Kai Back To Life

Goku and King Kai in Dragon Ball Z: Bojack Unbound

Now, this comes down to pure negligence. When Cell threatens to self-destruct and take the entire planet with him, Goku uses Instant Transmission to teleport himself and the villain somewhere else. The only place he can think of is King Kai's world, thereby dooming them both.

The characters have used the Dragon Balls countless times to bring back those whom the villains have killed. Never once has Goku suggested resurrecting the Lord of Worlds, yet he still uses his planet as his own private gym. That's gratitude for you.

1 Absorbing A Spirit Bomb

Goku Absorbing the Spirit Bomb in Dragon Ball Z: Super Android 13

The movies' place in the continuity is already quite spotty at best, and this doesn't help their case. Goku pulls this nifty trick out of nowhere to dispatch Super Android 13. It starts as a normal Spirit Bomb, gathering energy from the planet into a colossal ball. He then absorbs the energy into his body, powering himself up to beat the bionic baddie.

The hero has never used the Spirit Bomb like this before or since. It'd be helpful as a power booster whenever things get tough. Instead, Goku just chucks it at people. Is this unimaginative or just plain forgetful?

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