Rhythm and Meter in La Belle Sans Merci

The poem has a different scheme in which subverts the traditional ballad form. The fact that stanzas end so quickly, creates an emphasis on them , which shows how Keats wanted to alter the pace. Also extends the meaning of the poem as it  suggests what is going to happen (foreshadows) in a way, that everything is going to end very quickly, and all  of a sudden.