Why Are Some Stories Incomplete or Dispersed in the Qur’an?

Why are some stories incomplete or dispersed in different places in the Qur’an?

The Qur’an is the single greatest book. It discusses everything that one needs. One of the ways Allah (Exalted be He) teaches us lessons is through stories.

However, many of these stories are incomplete or are dispersed in different places in the Qur’an. Is there a reason for this?