Beyond hospital admissions being overwhelmed in Hubei, the rate of infection spreading probably far exceeded their ability to test everyone and as a result there were probably considerably more infections than the official numbers.

eg from Jan 26

>Prof Neil Ferguson, a public health expert at Imperial College, said his “best guess” was that there were 100,000 affected by the virus even though there are only 2,000 confirmed cases so far https://www.theguardian.com/science/2020/jan/26/coronavirus-...