At its core, sync is music solving a problem inside a piece of media.

That problem might be: make this brand feel modern, make this scene feel hopeful, make this trailer feel intense, make this recruiting video feel inspiring, make this product feel premium.

The specific problem changes every time, but the fundamental nature doesn't.

Your music is being hired to do a job, and the musicians who build sustainable sync careers are the ones who understand that early and build their approach around it.