Why do chord progressions work?
First up, chords in a progression work together because they're in the same key. The notes in the key (the scale) are put together to build that key's chords. So if I'm writing a song in the key of C major, I'll use chords made up of the notes from the C major scale.
What is the use of chords in music?
Why Are Chords Important? They're important for developing the structure of a song and helping to define different sections of a song with the use of chord progressions. A chord progression is a series of chords played in a sequence. Progressions are used to add harmonic content to a song.