Why does Japan have ａ lot of earthquakes?

The Japanese archipelago is situated along the North American Plate and the Eurasian Plate.
Squeezed in under these plates are the Pacific Plate and the Philippines Sea Plate, whichmakes the landforms unstable, causing a lot of earthquakes in and around the area.
There are also many active faults in the strata that form the land of Japan.
An active fault is a fault that has shown traces of activity during the past several hundred thousand years, and is likely to start moving in the future.
The cycle of its activity is said to be once every thousand years.
The Great Hanshin-Awaji Earthquake in January 1995 was caused by such an active fault.