PCI DSS: Merchant Levels Explained
Merchant levels are based on the volume or number of card transactions for each card brand over a 12-month period. As the number of transactions increases, it makes sense that the risk of a data breach is also increasing, therefore, the fact that the PCI DSS requires additional steps to maintain and verify PCI compliance also makes sense.
PCI DSS
Methods for Attesting Compliance about the PCI DSS: Merchant Levels Explained