An effective opening establishes an appropriate first impression. Barāʿat al-istihlāl additionally hints at the central purpose. Takhalluṣ is a coherent thematic bridge from prelude to main objective; iqtiḍāb lacks that full integration.
An effective ending requires completed meaning, suitable expression and a final impression consistent with the speech’s aim. A concluding prayer for a praised person may be particularly apt when it follows naturally from the virtues already described, rather than standing as an unrelated formula.