One more question to plate tectonics

 

One more question for plate tectonics

It is beltway, it takes years to built up stresses at plate boundaries, inside the crust.When these stresses are released by way of movement and Earthquake, it takes several years to built up stresses again
Now question is...
Why there are frequent 6+ quakes at locations like PNG ,Tonga etc.?
Why and how the stresses are built-up so fast.
If you have doubt ,take out records for both places and check.

Now here is my explanation
At such locations ,like Japan ,where more plate boundaries meet ,the structure is very week.So ,whenever there is little more tidal pull nearby ,it gives a way first ( being weakest)
Hence more major quakes at these locations
for more
https://Earthquake-prediction.blogspot.com