This has nothing to do with the nature of chords. In jazz theory, some different chords are often used. The main purpose is to make harmony (chord) progress regularly in one part, such as scale progress and semitone progress.
This is used here for chromatic series 4~4.
For example, if the original E7 goes to Am, it will be used as E7+9~E7-9~Am, so that a sound becomes 5~4~3.