How to Define a Role Before You Hire: What the Job Description Leaves Out
Most hiring processes are built on a document that was never designed to make a decision. The job description is written to advertise the vacancy, to satisfy a grading process, or by copying the last one, and it does those jobs adequately. What it almost never says is what the role will actually require of the person on a difficult Thursday: which decisions they will face with no clean answer, where the pressure comes from, and what the last person got wrong. Every later stage inherits that gap. The screen filters on credentials because credentials are what the document contains, the interview drifts to whatever the panel finds interesting, and any assessment built from it measures a generic version of the job.
This is a practical guide to closing the gap before the vacancy goes out: seven questions that produce a real definition of the role, how to turn the answers into requirements a candidate can actually be assessed against, and the mistakes that put the gap back. It sits before every other step in the process. What is an employee suitability assessment? and how to choose a pre-employment assessment tool both begin with "start from the role"; this is how.
Why a job description is not a role definition
A job description describes the shape of the post: title, reporting line, a list of duties, a list of requirements. A role definition describes what success in the post consists of, the pressures that come with it, the decisions that matter, and the environment the person will be working in. The first is a description of a box on an organisation chart. The second is a description of a job as it will be experienced, which is the only version a hiring decision can usefully be made against.
The requirements section is where the two diverge most. A degree, five years' experience and a background in the sector are not requirements of the job; they are proxies for capabilities the writer did not stop to name. Proxies are convenient to screen on and expensive in two ways: they exclude people who have the capability without the proxy, and they admit people who have the proxy without the capability. Skills-based hiring vs CV-based hiring goes into what changes when the proxies come out; the point here is that they only come out if the underlying capability has been written down in their place.
The seven questions
Put the hiring manager, someone who does the job or works alongside it, and whoever runs the process in a room for an hour and answer these in writing. Vague answers are the signal to keep going; a role that cannot be defined cannot be assessed, and the honest fix is more thought, not a longer advert.
1. What does success look like at ninety days, and at a year?
Not "settled in" or "performing well". Specific outcomes: the backlog cleared, the client relationship stabilised, the team's turnover stopped, the first release shipped. If the answer at ninety days is the same as the answer at a year, one of them is wrong. This question anchors everything that follows and it is the one most often skipped, because it forces the organisation to say what it actually wants from the hire.
2. Which decisions will this person face that have no clean answer?
Every role above entry level has a handful: the deadline that cannot be met without cutting something, the customer who is wrong but important, the colleague who is not pulling their weight, the budget that is short. List three or four. They are the material an assessment should be built from, and they are also the honest content of the interview. A role definition without them is a description of the job on a good day.
3. Where does the pressure come from?
Volume, deadlines, ambiguity, conflict, scrutiny, isolation: roles differ enormously in which of these dominates, and a person who thrives under one can fail under another. A customer service post is mostly volume and conflict; a compliance post is mostly scrutiny and ambiguity; a founder's first finance hire is mostly isolation and ambiguity. Name the one or two that dominate. This is what "can work under pressure" should have said.
4. Who does this person have to carry with them?
The stakeholder map: who they report to, who depends on them, who can block them, who they will have to say no to. Most role failures that are described afterwards as "not a fit" were stakeholder failures, and they were predictable from a map that nobody drew. For a senior role this question is most of the definition; assessing a senior appointment is largely about it.
5. What went wrong last time?
If the vacancy exists because someone left or was let go, the reason is the most valuable line in the whole definition and the one most likely to be left out because it is uncomfortable. Be specific and behavioural. "Could not prioritise once the workload doubled" is usable. "Was not right for us" is not. If the role is new, answer instead what has gone wrong in similar roles elsewhere in the organisation. Why new hires fail during probation sets out the usual shapes.
6. What kind of person thrives here, in behaviour rather than adjectives?
"Self-starter", "team player" and "resilient" describe nobody in particular. Answer instead in terms that could be observed: how much direction they will get and how much they will have to find for themselves; how fast the pace is and whether it is steady or spiky; how much structure exists and how much they will need to impose; how much detail the work rewards; and how comfortable they will need to be with disagreement. These are the dimensions on which a capable person can still be a poor match for a particular team, and they are worth writing down even if nothing in the process assesses them yet.
7. Of the skills listed, which two or three actually matter most?
A job description lists every skill as essential because there is no cost to doing so. A role definition ranks them, because the assessment and the decision have to. If communication matters more than technical depth for this post, say so and say why; if the reverse, the same. A definition in which everything is essential is a definition in which nothing has been decided.
Turning the answers into assessable requirements
The test of a requirement is whether a candidate could be observed meeting it. "Excellent communication skills" fails the test; "can explain a delay to an unhappy client in a way that keeps the relationship" passes it, because it names a situation and a behaviour. Rewrite each requirement in that form: what the person does, in what situation, to what standard. The decisions from question two and the pressures from question three supply the situations; the outcomes from question one supply the standard.
Then remove every proxy that is not a genuine requirement. A qualification the law requires, or a licence the work cannot be done without, stays. A degree that stands in for "can write clearly" goes, and "can write clearly" takes its place as something to be assessed. Proxies are also where adverse impact tends to enter a process, so this step is worth doing with the Equality Act check in mind: a requirement that is job-related and observable is far easier to defend than one that is customary.
Finally, fix the definition before the first candidate is seen and apply it to every candidate. A definition that is revised mid-process to fit a candidate someone likes has stopped being a definition, and the record of the decision will show it.
The mistakes that put the gap back
Copying last year's job description, which carries last year's proxies and none of what has been learned since. Describing the ideal candidate rather than the job, which produces a wish list no real person meets and a process that then compromises at random. Leaving out the hard part of the role because it might put applicants off, which recruits people for a job that does not exist. Defining the role around the person who just left, either to replace them exactly or to avoid them entirely, when the job has moved on in both cases. And treating the definition as the recruiter's document rather than the hiring manager's, when it is the hiring manager who will live with the result.
Where PRODICTA fits
PRODICTA starts from this definition and, where it is thin, helps you build it. You paste the job description and PRODICTA reads it into a profile of the role: what success looks like, the pressures involved and the decisions that matter. It then asks a small number of short, role-specific follow-up questions, the kind that take seconds to answer and change what is assessed: what the first ninety days need to deliver, where the biggest pressures are, what kind of person thrives in the team, and what has gone wrong with previous hires. You can weight the skills before anything is generated. The scenarios are then built from that profile rather than from a template, so the quality of the assessment follows the quality of the definition. How it works covers the steps, and the demo walks a real role through from job description to report.