Intercambio translates to 'exchange' or 'trade'. It is a transactional word that you would typically hear in business, banking, or when trading physical items.
In this heartbreaking track, Ivan Cornejo flips its everyday meaning by singing about an intercambio injusto (unfair exchange). He uses this metaphor to describe the pain of fixing his partner's broken heart, only for her to take that healed heart and give it to someone else. It is a highly creative way to describe the painful imbalance of a one-sided romance.
Have you ever felt like you did all the work in a relationship just for someone else to get the benefit? That's the heart of Ivan Cornejo's song. He sees his ex with a new person and realizes she looks happier than she ever did with him. The most painful part is his feeling that he was just a temporary fix. He sings, "duele saber que yo te arreglé el corazón / Y tú sin pensarlo se lo diste a él" (it hurts to know that I fixed your heart / and you, without thinking, gave it to him). He calls this an "Intercambio injusto" (Unjust exchange), and it's a perfect title for this feeling.
He feels completely erased from her life, as if they never even knew each other. He asks, "Cómo pasamos de decir 'Te amo' a ser dos extraños" (How did we go from saying 'I love you' to being two strangers?). The feeling is so strong that he wishes he could go back in time and avoid her completely, just so he wouldn't have to feel the pain of loving her now. He gave her everything, and he feels like she just took it all and left.