Experts expressed concern of the network's operational efficiency. In 2016, Chinese railways carried almost 2 trillion ton-kilometers of freight and over 1 billion passenger-kilometer of passengers, making it one of the world's most intensively used freight and passenger railway networks in the world. However, the rail staff productivity upon railway track infrastructure index in China is less than 0.05, being the lowest among the countries with significant railway construction. The government also articulated the importance and urgency of assuring the capacity of railway staff, especially their familiarity with telecommunication and signaling testing in the official investigation of the Wenzhou train collision. In addition, it is hard to identify problems in the construction process, given the distribution resource planning system needed for rapid railway building and assembling. Suppliers and manufacturers blame each other for any problem detected in the trial operation, while tracking the construction process to every single detail is an almost impossible job for inspectors.