This is what happens when reporters try to distill very complex subjects into a few sentences for laymen readers.
The ability of a fault to release energy is related to the length of the fault. The amount of energy transmitted to a site depends on a number of factors, including the type of fault movement, the distance from the site, and the foundation conditions.
When evaluating a structure for seismic loading ALL potential faults are looked at and complex calculations made to determine the most critical ground motions. A short close fault may be more critical than a bigger one far away.
This is a young science and each earthquake allows new evaluations worldwide. Upgrades then have the potential to make facilities safer over time.