Why does Goku’s tail not grow back?

Why does Goku’s tail not grow back? It is thought that the bodies of Saiyans, who are a fighting species, decided that their tails are unnecessary appendages. If you want the out of universe answer to your question, then Toriyama disliked drawing tails. He would always try to find scenarios in the series to not include the tail.

It is thought that the bodies of Saiyans, who are a fighting species, decided that their tails are unnecessary appendages. If you want the out of universe answer to your question, then Toriyama disliked drawing tails. He would always try to find scenarios in the series to not include the tail.