Inspite of longe range order in the arrangement of particles why are the crystals usually not prefect ?

Inspite of longe range order in the arrangement of particles why are t

1.	Inspite of longe range order in the arrangement of particles why are the crystals usually not prefect ?
Answer» Answer :This is because when CRYSTALLISATION occurs at a fast or MODERATE RATE, the constituent particles may not get sufficient time ARRANGE themselves in a perfect order .