What Do Great Songs Have In Common?

Great songs have a lot in common. Most of them speak a global language that we all, as listeners, likely started recognizing and internalizing while still in the womb.
The language of songwriting has been evolving over tens of thousands of years. Songs passed between generations and tribes contained the blueprints of musical tradition that are still reflected in the structures of contemporary music, and still influence our reaction to every piece of music we will ever encounter. This is a shared subconscious global knowledge of rules and theory, that allows us to judge whether a song sounds great or doesn’t. This global subjectivity is important to keep in mind, because as listeners of music, we are all experts of what moves us. The same is true whether you identify as writer or audience.
Our appreciation of music is so deeply internalized, we take it for granted. But, like fish that don’t know they’re wet, very few of us carry the awareness necessary to articulate why a song works, much less know how to shape our own songs and compositions by these rules.
The same is true for songs we don't like... When a song falls out of a subconsciously predicted pattern, most listers will just tune out. It’s an instant death, usually with no redos or makeovers. A song that loses its audience is a song not heard. You may as well be playing for your bedroom mirror.
Choosing to learn and harness the rules and conventions of songwriting will keep more people engaged, and make your songs, your voice, and your unique perspective accessible to more people than you might think possible.