Pegging and planning exceptions: understanding why a proposal exists

A planning result may recommend producing 200 units or obtaining a component by a particular date. Before acting on it, the planner needs to understand the demand behind the recommendation and the constraint it addresses.

Pegging traces the relationship between demand and proposed or available supply. Planning exceptions identify conditions that require attention. Together they make the plan explainable.

Demand-to-supply relationships

DNA planning results include pegging information. This helps the planner understand which requirement a supply proposal serves rather than treating each planned order as an isolated quantity.

The relationship matters when priorities change. If a customer postpones an order, the planner needs to know which production or component proposals were intended to support it. Some supply may also serve other demand, so cancelling everything associated with one customer without reviewing the relationship could create another shortage.

A practical dependency

Two customer orders require the same assembly. One is due next week and the other next month. A component delivery arrives between those dates.

The total component supply may cover both orders eventually, but the earlier order still faces a timing problem. Pegging and exception information help identify the affected demand instead of describing the whole product family as simply sufficient or insufficient.

What an exception means

An exception is a signal that the selected planning assumptions and current data produce a condition requiring review. It may concern timing, shortage, or another documented planning constraint. It is not automatically an instruction to override a control or create an urgent purchase.

The planner needs to understand the cause. An incorrect lead time can create a false urgency. An omitted incoming supply can create an unnecessary proposal. A genuine shortage can require a new commitment or a revised promise.

Scope and repeated runs

Configuration warnings deserve attention alongside material shortages. A run that omitted a requested source answers a narrower planning question than intended. Repeating it without resolving the missing input does not supply that evidence.

Planning results can change when demand, stock, supply, or parameters change. A difference between runs should therefore be interpreted against those inputs. It does not necessarily indicate an error.

The horizon and item scope also determine which relationships are visible. A result from a limited run should not be presented as a complete company-wide supply plan.

From analysis to decision

A useful planning decision identifies the demand at risk, the proposed response, the owner, and the assumptions that justify it. DNA's relationships provide evidence for that decision.

The goal is a plan that purchasing, production, and sales can understand together. Pegging explains the reason for the supply; exception review explains where the plan needs judgement.