Why have so few countries achieved a soft landing on the moon?

Indian Prime Minister Narendra Modi has said he has confidence in his country's space program, after it lost contact with its lunar lander minutes before it was about to touch down on the moon. The fate of the lander and rover is still not known. So far, only three countries have achieved a soft landing on the moon. Why is that? Xu Yansong, director-general of the Asia-Pacific Space Cooperation Organization, shared his views.