Among candidates the interview was long regarded as a formality. The way the grades work says otherwise. An "inadequate" grade means rejection however high the written score. Conversely an "excellent" grade means success regardless of it. That is where written rankings get overturned.

The conditions for each grade

Panel members rate each of five assessment items as high, medium or low. The grade is decided by combining those ratings.

• Excellent — a majority of the panel rate all five items "high". Final success regardless of the written score.
• Inadequate — either of the following: (1) a majority rate two or more of the five "low"; (2) a majority rate the same single item "low". Rejection regardless of the written score.
• Standard — everything that is neither of the above. Places remaining after the excellent candidates are filled in order of written score.

Look at that structure again and the practical objective becomes clear. For most candidates the goal at interview is not to be rated "excellent" but to avoid "inadequate". A standard grade leaves the written score to decide.

The second condition for "inadequate" is the dangerous one

Widely missed. "Inadequate" is not only about receiving "low" on two or more items. If a majority of the panel rate the same single item "low", that alone produces an inadequate grade.

What that condition means is plain. If one weakness is visible in the same way to several panel members, you fail. For instance, answers that are fine in content but consistently lose marks on manner, or answers that keep sliding past the point of the question.

So the rational preparation strategy is removing an obvious weakness rather than maximising a strength.

The five assessment elements

The elements are set out in the relevant legislation and are broadly these five.

• Attitude and outlook as a public official
• Specialist knowledge and the ability to apply it
• Accuracy and logic of expression
• Courtesy, conduct and diligence
• Creativity, determination and potential to develop

As the list shows, only one item tests knowledge. The other four are attitude, expression, diligence and potential. The ability that got you through the written exam generally protects the knowledge item. The difference is made in the rest.

Practical ways to avoid an inadequate grade

• Answer the question first. Long background explanations lose marks on "accuracy of expression". Conclusion, then reason, then example is the safe order.
• Say when you do not know. Bluffing and then collapsing under a follow-up costs more. "I would check that" is an answer used at work too.
• Know what the organisation does. Not knowing what the job series actually involves undermines both "attitude" and "potential to develop" at once.
• Manage the length of answers. Too short and it reads as indifference; too long and the logic becomes the problem.
• Keep your manner consistent. Relaxing your expression on the last question is something several panel members see together.

In summary

The structure is this: an excellent grade overturns upwards, an inadequate grade overturns downwards. And a single item seen as "low" by several panel members is enough to fail. So the goal of preparation is not a dazzling answer but leaving no obvious weakness. Exam subjects and changes to the system are covered in Civil Service Exams.