How do you distinguish between minor earthquakes which are followed by major earthquakes, and minor earthquakes which aren't followed by major ones?

The rule-of-thumb is that there are in the order of 10.000 3 Mw earthquakes for every single 7 Mw earthquake. How do you decide which 9.900+ ones to discard? How are you going to distinguish a critical precursor from a 2.3 Mw Taylor Swift concert[0]?

[0]: https://edition.cnn.com/2023/07/27/entertainment/taylor-swif...