Why didn't Vegeta's tail grow back?

[ahill1]

When Vegeta had his injuries healed in an alien planet, he stated his tail would grow back... but it never did. Did Toriyama just forget about that?

 

[Captain Cadaver]

Considering it was after this that Vegeta started to make gains that he cited as "no normal increase", as well as comparing it to how the U6 Saiyans have been shown to evolve, it can be concluded that the tail not growing back is some evolutionary sign of a Saiyan coming into the threshold where they have the potential to become a Super Saiyan and not be dependent on the Oozaru form.

That's the best in-universe answer I can think of. The meta answer is obviously got tired of drawing tails and chose to just do away with them when possible.

 

[GreatSaiyaman123]

(12) What happened to Vegeta’s tail after he was defeated on Earth? –Marc LaCroix, Nova Scotia, Canada

The tail lets you gain tremendous strength instantly by transforming into a giant ape, but the risks are equally great–you’ll lose your strength if it’s squeezed. Once you’re as powerful as Vegeta and Goku, the tail just gets in the way. It is thought that the bodies of Saiyans, who are a fighting species, decided that their tails are unnecessary appendages.

 

[Boo Brand Milk]

No tweezers

 

[Captain Cadaver]

you’ll lose your strength if it’s squeezed. Once you’re as powerful as Vegeta and Goku, the tail just gets in the way.

Despite the fact both of them had strengthened it through training as to lose the weakness.

 

[Let's Go Fearless!]

Vegeta abusing the Zenkai boost must have something to do with it. There's no answer to this question in universe wise. Who knows maybe Toyo might touch this subject soon.

 

[Captain Cadaver]

Vegeta abusing the Zenkai boost must have something to do with it. There's no answer to this question in universe wise. Who knows maybe Toyo might touch this subject soon.

He did mention how the U6 Saiyans evolved to lose their tails after finding it unnecessary, though given Tracetaro's priorities, that's probably the most we'll ever get on the matter.

 

[Let's Go Fearless!]

Vegeta abusing the Zenkai boost must have something to do with it. There's no answer to this question in universe wise. Who knows maybe Toyo might touch this subject soon.

He did mention how the U6 Saiyans evolved to lose their tails after finding it unnecessary, though given Tracetaro's priorities, that's probably the most we'll ever get on the matter.

True but we still haven't got an explanation for U7 Saiyans though. With a promise from Vegeta to visit Planet Sadala so it's a possibility that we'll get an explanation about this.

 

[Symbiote]

Maybe after a certain age they just stop growing back. Goku and Gohan’s Only grew back 2 or 3 times when they were children and they stopped.