If it technically predicts earthquakes but can't tell you which of the earthquakes will be strong enough to warrant evacuation, then will people heed the warning for the big one after they've had a few evacuation notices for imperceptible earthquakes? It's a "boy who cried wolf" problem.

The vast majority of earthquakes are very weak, so predicting the time and area of earthquakes seems worthless if they can't accurately predict the magnitude as well, with very few false positives.