Yes, exactly. There is a weird conflict of interest thing happening with a lot of public-facing security assessment work. The client wants a clean bill of health. The delivery consultants can't honestly sell that, at least not without a huge project scope stretching into double-digit person/months. But the firm wants to sell engagements, and public reports are a condition of the engagement.
So we have this phenomenon of "audit reports" that are really anything but that. Very few people in the industry know how to read them (for instance, how to locate and evaluate the scope of the project). But they're effectively used as seals of approval by clients. Which creates an even bigger incentive for firms to sell them, to the point where there are firms that almost specialize in doing them.
PCI is closer to the audit model, and yet even less effective than the pentest model, because the standardized delivery model created a race to the bottom effect in the market.
My oddball position on this stuff: firms shouldn't do external reports at all, and clients should just be able to post their internal reports.