Since all debris will return to near the collision point approximately every 90 minutes, there will be further collisions of bits of debris that will tend to re

Since all debris will return to near the collision point approximately every 90 minutes, there will be further collisions of bits of debris that will tend to reduce the size of the bits of debris and speed up the decay. This will be more pronounced if the original objects that collided have orbit planes that are nearer orthogonal.