Groothandelsgebouw is a megastructure in the traditional sense, that is, the initial stage of the design starts from the building volume, and its scale, function, construction method, social significance, and other characteristics all meet the definition of megastructure. The project Cube Houses, starting from a single small unit, continue to grow and superimpose under the control of the system and structure. Under the logic completely opposite to Groothandelsgebouw, another megastructure is finally formed. At this point, it is more like the Metabolism trend in Japan. It can be said that the two are different in terms of design concept, generation logic, and building type, but they all encountered the most common problems of megastructure architecture—too much pursuit of form and logic, and the loss of thinking and design of the most basic space. Megastructures are often easily reduced to a symbolic monument without regard to human scale. Therefore, this is also the problem that must be solved in the design of megastructures—How to combine large-scale space and small-scale space in the design, and use “dual scale” to design? The scale of each spatial element should be relatively uniform, between the separate parts, between parts and whole, and with the strive to be unified and coordinated on the overall scale.
However, these two megastructure buildings in Rotterdam, an extremely inclusive city, can be said to have used the advantages of megastructure concepts. In the process of urbanization, these two megastructure buildings have achieved their goals and resolved the problems that need to be solved at that time. In the later stage of use, some renovations have also been relatively smooth, and they still play their role in the city and still retain vitality in their neighborhood.
All in all, the megastructure has appeared very early in the history of human civilization, and its symbolic meaning is the most fundamental reason for its birth. Until the twentieth century, the rise of modernist architectural theory provided a theoretical basis for the imagination of megastructures, and the rapid progress of science and technology provided the feasibility of megastructures. In those eras when imagination and creativity sprang up, along with human's longing for utopian life and the pursuit of higher civilizations, the theory of megastructures continued to develop, and one after another, aggressive and bold proposals were constantly being proposed. Architects, planners, and theoretical scholars were constantly thinking about the larger city and the future. However, after 1960, some megastructure projects were completed all around the world, and some of the disadvantages of megastructures were gradually exposed. After fantastical imagination, people began to reflect on the feasibility of the megastructure and its adverse effects. And as people-oriented thinking gradually became mainstream, more and more architects started to pay attention to the relationship between human and architecture, space, materials, atmosphere, etc. These considerations of details also caused more and more people to criticize the megastructure. Therefore, after experiencing the golden age of the twentieth century, the trend of megastructure theory is gradually fading. Today, there seem to be fewer people still discussing megastructures. In the context of artificial intelligence, the explosion of information, and the pursuit of capital for profit, there is already too much at the material level, but our cities are increasingly lacking in spirit, humanity, and emotion. Our grand imagination of the future seems to have stalled, and those idealistic times are gone. The megastructure has not been able to be completely discussed, researched, and summarized by the academic community before it has gradually become the dust of history.
Karl Mannheim once stated: “Today's utopia is likely to become the reality of tomorrow, and various utopias are often just the truth of premature birth.”  In this day and age, perhaps we cannot just stop the imagination and exploration of megastructures. Constantly questioning, criticizing, updating, and improving the theory and practice of megastructures and megacities may be one of the best ways to explore the future living environment of mankind.