Here is what Messi said in the interview with newspapers Diario Sport and Mundo Deportivo:

"I heard that they had to sell players or lower players' salaries and the truth is that I didn't want to go through that, nor take charge of obtaining something that had to do with all that."

New York Times interprets those words clearly: "he did not want to be held responsible for forcing Barcelona to adjust its squad simply to accommodate him." That is a very valid reason. This is a very good lesson for all Barca players and fans. So damn cool! The GOAT indeed. Thank you!