ManualDoc:W800003

Volume discounts are incentives intended to encourage the purchase of goods in greater quantities. This incentive is normally offered to pass on some of the economic efficiencies gained through larger orders, to improve customer relations, and to increase total volume of sales.

Volume Discount is an Openbravo "Advanced Feature" implemented through below listed application dictionary elements:

• a window named "Volume Discount"
• and a Tab in the Business Partner window.

Those elements are hidden by default, therefore they way to make it work is to unhide them as described here.

There is a How to article which describes how to use volume discounts in Openbravo.