Credentials that dissolve, and authority that spreads

Two late-stage signs: qualifications that thin out under inspection, and a narrow standing spent everywhere.

Credentials are weak evidence, but they are not nothing, and the informative thing is usually not the credential itself. It is what happens when you look at it closely. Sometimes the qualification is real, current and directly relevant, which is a small positive. Sometimes it turns out to be from an unrelated area, or long lapsed, or issued by a body that exists mainly to issue it, or described in language carefully constructed to imply more than it says. That last case matters most, because it shows an intention to be misread, and someone willing to shade their own biography is telling you something about how they will handle everything else.

The other late sign is the spread. Standing earned narrowly gets spent broadly: a person known for one demonstrable achievement begins pronouncing on unrelated subjects, and the audience carries the deference across, since the deference attached to the person rather than the domain. This can happen without any deliberate deception at all. Being treated as an authority is disorienting, and the general question is always more interesting than the narrow one.

None of these signs is conclusive alone, and it is worth saying clearly that most people who set off one of them are not frauds. The pattern matters when the features cluster: the single explanation, the insiders and outsiders, the hostility to questions, the credential that thins under inspection, the authority that has drifted far from where it was earned. One is noise. All five together is a shape, and once you have seen the shape a few times you will recognise it early, which is the entire practical benefit of learning it.