However, there were arguments regarding the necessity of widespread overarching protection measures with less strict stipulations, because the designation system for important cultural properties at national level had strict criteria, and was not powerful enough to preserve the rapidly decreasing number of modern buildings.
しかし、急激に消滅しつつある近代の建造物の保護にあたっては、国レベルで重要なものを厳選する重要文化財指定制度のみでは不十分であり、より緩やかな規制のもとで、幅広く保護の網をかけることの必要性が議論された。