Final answer:
Mali architects had disadvantages due to the need for frequent maintenance of structures made from sunbaked mud brick and political instability, which threatened the preservation of architectural heritage.
Step-by-step explanation:
Mali architects faced distinct disadvantages due to environmental challenges and material limitations. The inherent properties of local building materials, like sunbaked mud brick, required constant maintenance and reduced the longevity of structures. Mali's periodic heavy rains necessitated annual repairs, especially notable in the case of the Great Mosque of Djenné, which was coated afresh with mud every year. Additionally, political instability and conflict, as seen in attacks on historical and religious sites in 2012, posed threats to maintaining architectural heritage.
Among the factors leading to the collapse of the Mali Empire, the succession of weak rulers and ensuing political instability seem paramount. This weakened central control and led to difficulty in maintaining the trade routes that were the economic lifeblood of the empire. The rise of powerful neighbors, internal rebellions, and the arrival of the Portuguese accelerated the decline of the empire. Mansa Musa's succession by his unpopular brother Mansa Sulayman typified the kind of leadership that could not sustain Mali's former glory, further destabilizing the empire both politically and economically.