Why do the verses of a single Surah address multiple topics without correlation between them?

A single Quranic Surah addresses multiple issues, and the topic of coherence (Munasabah) between verses is a matter of significant disagreement among scholars:

1. One group believes there is no coherence, because the Qur’an was revealed in piecemeal fashion according to events. 2. Another group believes that coherence exists, provided there is a unity of subject matter; otherwise, there is no connection. 3. A third group believes that coherence exists between all verses and Surahs as a precise manifestation of miraculousness, and that the Mushaf (codex) is arranged according to divine wisdom. 4. A fourth group believes that the Qur’an has a general and specific system within a single Surah and between Surahs, and coherence is part of this system. Thus, the Qur’an is a single discourse with coherence and arrangement in its parts.

One can refer to the book "Al-Naba' Al-Azeem" (The Great News) by Dr. Muhammad Abdullah Daraz, who elucidated the rhetorical characteristics of the Qur’an, including the multiplicity of themes within a single Surah while organizing them into a single, beautiful context, as one aspect of its miraculousness.