How do CPQ Approval Processes work and how do they differ from standard Salesforce approvals?

CPQ introduces its own approval framework via the SBQQ__Approver__c object and SBQQ__ApprovalCondition__c objects, which complement (or replace) standard Salesforce Approval Processes for quotes. Key differences and features:

1. Approval Variables: Evaluate conditions across quote lines (e.g., "if any line has a discount > 30%") — standard approvals cannot easily aggregate line-level data.
2. Approver Object: Defines who approves and under what conditions; approvers can be users, roles, or groups.
3. Chain vs Parallel: Approvers within a step can be configured as sequential (chain — each approves in order) or parallel (all must approve simultaneously).
4. Quote Approval Status: The Quote's approval status field (SBQQ__ApprovalStatus__c) reflects the overall state (Pending, Approved, Rejected). Approvals can be triggered automatically when a quote is submitted or when the "Submit for Approval" button is clicked. CPQ also supports standard Salesforce approval processes layered on top of the CPQ approval object for simpler use cases.