Based on the pricing source chosen in the Billing Settings, the pricing information is fetched from the order line item (OLI) or asset line item (ALI). When the pricing source is set to OLI, Billing fetches all the information, including the pricing information, from the OLI. If the pricing source is set to ALI, Billing fetches the pricing information from the ALI. For more details on pricing sources, see Managing Pricing Source.