Supplier Scorecard: Design Rules and Process Limits

A supplier scorecard converts a supplier relationship into numbers that can be reviewed and acted on. Without it, quality problems and late deliveries are handled as individual events, and the pattern that links them is never seen.

The measures should be few, objective and taken from data the supplier already has, so that the conversation is about the numbers rather than about their validity.

What to Measure

Four measures cover most of the risk: on time delivery, quality measured in defective parts per million, responsiveness to a corrective action, and commercial conduct. Anything beyond that is usually a variation of one of the four.

The definitions have to be agreed in advance, particularly for on time delivery, since a delivery that arrives complete but late is a different failure from one that is partial.

On Time Delivery

The measure should be against the date the supplier committed to, not the date the customer requested, because the commitment is what the supplier controls. The measure should also record the quantity, since a partial delivery that meets the date is still a shortage.

The threshold for a delivery to count as on time should be defined, since a shipment that arrives on the day but after the line has stopped has already caused the problem.

Quality and PPM

Defective parts per million is calculated from the returns and the rejects, and it should be reported by part rather than as an average. An average hides the single part that is causing the problems.

The calculation should include the defects found in production as well as those returned by the customer, since a defect found internally is still a defect from the supplier.

Corrective Action Response

The measure is the time to acknowledge and the time to close, together with the effectiveness of the action. An action that is closed quickly and recurs has not worked.

The scorecard should record the recurrence, because a supplier who closes actions without changing the process will otherwise appear responsive.

Commercial and Administrative Conduct

Price changes, notification of a process or material change and the accuracy of documentation all affect the relationship. A supplier who changes a material without notification, as described for supplier qualification, creates a risk that no quality measure captures.

These items are softer than the others and should still be recorded, because they predict future problems.

Scoring and Weighting

The weights should reflect what matters for the specific part: a commodity part is mostly a delivery question, while a critical part is mostly a quality question. A single weighting applied to every supplier produces a misleading ranking.

The score should be simple enough to be explained in one paragraph, since a score that cannot be explained will not be accepted.

Review Rhythm

The review should have a fixed rhythm, with the data circulated before the meeting so that the discussion is about the actions. A meeting that is used to present the data spends its time on what everyone could have read.

Where the score is poor, the outcome should be a defined action with an owner and a date rather than a general request for improvement.

Consequences

The scorecard has to have consequences to be credible, whether that is additional inspection, a reduced share of the business or a requirement for a formal improvement plan.

A scorecard that never changes anything becomes a document that the supplier reads and discards. This is the same principle that applies to any measurement used internally.

Records

The scorecards should be retained with the delivery and quality records, so that a trend across years can be seen. A supplier who improves and one who declines look the same in a single month.

They belong with the quality records described for manufacturing tolerances and with the audit evidence discussed for process audits.

Process Control and Verification

Documenting the assumption is part of the design work, and a short note on the drawing prevents a question that would otherwise arrive a day later and cost a day of schedule. The process window is set by the narrowest step in the flow, so an improvement anywhere else shows up as margin rather than as yield until that step is addressed.

A short note on the drawing about handling, storage or packaging is often worth more than an extra decimal place on a tolerance. Where a value sits close to a process limit, the drawing should say so, since the shop can then open the process window rather than working to a nominal figure that carries no tolerance.

A stack-up that is drawn rather than described removes most of the ambiguity from a quotation, and it lets the fabricator price the board against the dielectric and copper weights that will actually be used.

Checks Before Release

The checks that matter are the ones performed on the product rather than on a sample kept for the purpose, because a coupon that travels with the panel is the only evidence about that panel. Where a requirement can be measured, it should be measured at the point of manufacture and recorded against the board or the lot it applies to.

A parameter that is set once and never re verified drifts, and the drift is usually discovered by a defect rather than by the record. The tooling, the material and the profile form one system, and a change to any of them should be assessed against the other two before it is released.

FAQ

How many measures should a scorecard have? A small number, because a long list dilutes the attention that the important measures deserve.

Should the score be shared with the supplier? It should, in full, since the purpose is to change behaviour rather than to keep an internal record.

What if the supplier disputes the data? The definition should be agreed in advance, and the data should come from records both parties can see.

What is the most useful single measure? On time delivery, because it is objective and it affects the schedule immediately.