Why didn't anyone inform the Sichuanese during the earthquake?

So far, earthquake prediction is still a worldwide problem. Earthquake prediction must include both time, place and intensity. Because of the complexity of earthquakes, some earthquakes are predictable, while others are not. At present, the accuracy of global earthquake prediction is only over 20%. At present, including the United States, Japan and other developed countries, earthquake prediction is still in the exploratory stage, far less accurate than weather prediction. In recent years, some scientists in the world hold negative opinions on earthquake prediction. Some people even published a paper on "the earthquake is unpredictable", which clearly put forward the argument that "the earthquake is unpredictable". However, some seismologists have affirmed the achievements of earthquake prediction, and believe that the short-term prediction of earthquake location, time and magnitude will eventually be realized, while the long-term prediction is more prominent.