What does Egypt's decision to build Aswan Dam give us?

A large number of Aswan Dams in Egypt were built in the early 1970s. On the surface, the dam brought cheap electricity to the Egyptian people, controlled floods and droughts, and irrigated farmland. However, the dam actually destroyed the ecological balance of the Nile valley, which triggered a series of disasters: due to the sediment and organic matter deposited at the bottom of the reservoir, the oases on both sides of the Nile lost the source of fertilizer-hundreds of millions of tons of silt, and the soil became increasingly salinized; Due to the lack of sediment supply in the Nile estuary, the delta plain of the Nile estuary shrinks inland, which makes factories, ports and national defense fortifications in danger of falling into the Mediterranean Sea. Due to the lack of salt and organic matter from land, the annual output of sardines decreased by 6,543,800 tons. Due to the dam barrier, the living water in the lower Nile turned into a relatively static "lake", which provided conditions for the reproduction of Schistosoma japonicum and Anopheles, leading to the prevalence of schistosomiasis in the reservoir area. The disastrous consequences of the construction of this dam in Egypt have made people deeply sigh: one step away, lifelong regret! Case thinking: Hint: In reality, decision-making is often multi-objective, and people's understanding of what kind of predetermined goal the decision-making result should achieve is often related to value judgment. Any decision-making scheme may bring all kinds of negative effects while achieving the expected positive effects. Please carefully analyze this case according to the tips and the management knowledge you have learned, especially the content of decision-making and your own point of view.