* To create a sense of order and structure. In a world that can often seem chaotic and unpredictable, poetry provides a sense of order and structure. The regular rhythm and meter of poetry can help to create a sense of calm and peace.
* To make their poetry more memorable. Poetry that is written in a rhythmic and metrical pattern is more likely to be remembered than poetry that is not. This is because the rhythm and meter help to create a memorable melody that can be easily recalled.
* To add emphasis to certain words or phrases. The rhythm and meter of poetry can be used to add emphasis to certain words or phrases. This can be used to create a variety of effects, such as highlighting important ideas, creating a sense of urgency, or adding a sense of drama.
* To create a musical effect. Poetry can be seen as a form of music, and the rhythm and meter of poetry can be used to create a musical effect. This can be used to add beauty to the poetry, to create a sense of atmosphere, or to simply add enjoyment to the reading experience.
In addition to these reasons, early poets may also have used rhythms and meter because it was simply the convention at the time. Many early poems were written in traditional forms that had specific rhythmic and metrical patterns, and poets were expected to follow these patterns in their own writing.