Why did Malcolm X wait to tell his story?

As we know his story was told by A. Harley so he didn't wait for something, really, but I think he gave the order to publish his autobiography after he learned from mistakes and experiences he went through. Also, He knew his story showed another perspective of the world, a perspective of a black man who was excluded and forced to went into the drug world and crime to survive in a society that benefits white people just because of their skin color. That is why his book made such an impact at that time and the current time because is so personal and makes us feel what he felt when he was living those injustices.