What is the fundamental distinction between a Primary Cost Element and a Secondary Cost Element in SAP Controlling?

• Primary Cost Elements: Arise from primary expense transactions originating in Financial Accounting (FI)—such as salaries, rent, or utilities—and flow directly into CO. Every primary cost element must have a matching Profit & Loss (P&L) G/L account in FI. • Secondary Cost Elements: Used exclusively within CO to perform internal cost allocations (such as assessment cycles, internal activity allocations, and overhead surcharges). They have no direct equivalent in FI P&L accounts because they track internal cost movement rather than external transactions.