It’s not clear why
In Turkey, this system was launched in 2021. Google says that on the same day, February 6, an earthquake warning was sent to millions of people in the country before the first aftershocks. However, BBC Newsnight journalists interviewed hundreds of people in the three affected cities and did not find anyone at all who would receive such an alert.
Android Earthquake Alert System Completely Failed in Case of Earthquakes in Turkey
At the same time, Google was unable or unwilling to provide journalists with clear evidence that the system worked, as they claim. There is only a document that shows 13 posts on social networks, where people wrote about the notifications they received. A Google spokesperson says it may be because people simply didn’t pay attention to the alert because of the magnitude of the events that followed.
Perhaps, given the huge impact of the first event, it just quietly happened in the background, while users were really paying attention to a lot of other things. In the end, I think this is probably the most likely explanation.
At the same time, the Google system was launched back in 2020, and has already managed to work out normally in other cases. Among other things, this is indicated by the messages of people in various social networks, and in the case of Turkey, there were practically no such messages. Moreover, if we talk about those same 13 messages, only in one user spoke about the notification that he received before the first earthquake. In other cases, the messages concerned the second.
Recall that the Google system is not just some kind of relay that should transmit an alert to Android users from some seismic activity research center. The point is that smartphones themselves act as a kind of mini-seismometers. There are a lot of them, they are all equipped with accelerometers and gyroscopes, and the Google system analyzes this data and can predict an earthquake, or at least notify people in neighboring regions immediately after the first shocks.