Are all the versions of a mith the same ?

ARE ALL VERSIONS OF A MITH THE SAME ?
We read the myth Theseus and the Minotaur in English and in Spanish. The two versions are not exactly the same.
One of the differences is the name. In the English version it is "Theseus and the Minotaur" but in the Spanish version it is "Theseus and the labyrinth".
Another difference is that the stories start and finish in different ways. For example, in the English version, the story starts in Troezen where Theseus lived when he was a boy while in the Spanish version the story begins when Theseus arrives in Crete to kill the Minotaur. Then, the English version finishes when Theseus arrives in Athens and he becomes the King while in the Spanish version he story ends when Theseus kills the Minotaur and he comes out of the labyrinth.
The number of characters is also different. Some characters do not appear in the Spanish version. These are the characters that are in Troezen and Athens in the English version. For example: Aethra, King Aegeus and in Crete, Phaedra (Ariadne’s sister)
Another important difference is that there is an element of magic in the Spanish version. The sword and the ball of thread that Ariadne gives Theseus are magical .This is not like this in the English version.
So we can say that there are different versions of the same myth but the message is the same: a true hero has many difficulties in life but he always tries hard and always risks his life to save other people.