Destino translates to "destiny" or "fate". It's a word that evokes a sense of purpose and the unknown, making it intriguing.
In the song, Aitana asks, "¿Cómo le escribo una canción al destino y le pregunto lo que quiere conmigo?" (How do I write a song to destiny and ask it what it wants with me?). This line beautifully personifies destiny, turning it into a character she can communicate with, adding a poetic depth to her quest for purpose in music.
Aitana spends this whole song arguing with herself about why she has to make music, and she keeps landing on the least glamorous answer. "No quiero fama tampoco dinero" ("I don't want fame or money"), she sings, right before "Y la única salida es hacer lo que quiero" ("and the only way out is doing what I want"). The song she is trying to write is addressed to fate itself: "Cómo le escribo una canción al destino" ("how do I write a song to destiny"), as if the thing deciding her life could be talked round by a good chorus.
The best line is the blunt one about what music is actually for. "La música es como el alcohol a la herida" ("music is like alcohol on a wound") does not promise it will feel good, only that it will work. From there she lists what songs do for everyone else, "Unas para reír otras para llorar" ("some to laugh to, others to cry to"), and then drops the pretence: "No es que yo te quiera, es que te necesito" ("it's not that I love you, it's that I need you"). She is talking to the music. By the end "Quiero" has repeated so many times it stops sounding like a wish and starts sounding like a job.