Whether the end of a song or a section sounds finished is decided almost entirely by its last two chords. And you can deliberately choose not to finish.
Writing has full stops and commas; music has "that's the end" and "there's more coming". The last few chords are what create the difference.
Three endings, back to back
Three versions of the same opening, changing only how they end. Each finishes to a different degree.
- Ends V → I (fully finished)
C | F | G | C
- Stops on V (something is coming)
C | F | C | G
- Ends IV → I (finishes gently)
C | G | F | C
The pattern a phrase ends with. V→I states the end; stopping on V says "there is more".
The skill of not finishing
If the verse ends with a full cadence, the song settles right there and loses the momentum into the chorus. That is why most songs end verses and pre-choruses on V or IV, handing over to the next section. When a song "never builds", too many internal full stops is a common cause.
ChordMelo varies the cadence by section
The same progression generates differently depending on the section you pick. Choose pre-chorus and it leans away from landing on the tonic at the end. Compare them below.
- Generated as a verse (settles)
C | F | G | C
- Generated as a pre-chorus (left hanging)
C | F | G | C
Generate with the pre-chorus setting. You get a melody that deliberately refuses to finish.
Generate a pre-chorus melodyV → I finishes completely. Where you do not want to finish, stop on V or IV and leave the listener expecting more.