What a second opinion actually costs — and what not having one costs later

Most people running a lean project team already believe, in principle, that an independent technical review has value. That's rarely the actual objection when it doesn't happen. The real hesitation is more practical, and worth taking seriously on its own terms rather than arguing past it. 

The real objection isn't the principle — it's the arithmetic

A small project team runs fast because it's small. Every additional cost gets weighed hard against a tight budget, and every additional voice in the room is weighed against the speed that comes from not having one. On top of that sits a specific, reasonable fear: that "independent review" means paying someone to sit in on your meetings for a few weeks and hand back a polished version of what your own team already believes, dressed up as outside scrutiny.

That fear is fair. It happens often enough in this industry that it's a reasonable prior, not paranoia.

Two different ways "independent" quietly stops being independent

There are two distinct failure modes worth naming separately, because they come from opposite directions and get missed if they're lumped together as one vague concern.

The first is the reviewer with something to protect. A reviewer who holds a construction contract, an EPCM relationship, or future work riding on staying in a client's good books has a structural reason to soften a finding the client doesn't want to hear — not necessarily dishonestly, but through the ordinary human tendency to avoid conflict with someone who controls your next engagement.

The second is the reviewer with something to sell. Some review and audit engagements are structured so the reviewer's fee, or the size of a follow-on contract, grows with the number of findings. That creates the opposite bias: an incentive to manufacture issues, or to inflate minor ones, to justify a bigger scope.

Genuine independence means neither incentive is present in the room. It's worth asking any prospective reviewer directly what they stand to gain if their findings come back clean, versus if they come back critical. If the honest answer is "nothing either way," that's what independence actually looks like in practice, not just in the engagement letter.

What a properly scoped review looks like

None of this requires a slow, expensive, all-encompassing audit. Done properly, an independent review is fast and tightly targeted — a focused check on the handful of assumptions that would actually do damage if they turned out to be wrong, rather than a line-by-line audit of everything in the study. Scoping it that way is what keeps it affordable and keeps it out of the way of a lean team's pace, which is precisely the two things a small project team is most protective of.

Weighing the cost against what it's actually insuring against

It's worth being specific about the number this is being weighed against, because "it might cost more later" is easy to wave away in the abstract.

Research into large infrastructure and industrial projects — including widely cited work from McKinsey — has found that such projects overrun budget by an average in the order of 80% and schedule by around 20%. McKinsey's mining-specific research paints an equally blunt picture: more than four in five mining projects come in late and over budget, by an average of 43%. A separate, peer-reviewed 2025 study modelling cost overruns specifically at the front-end engineering design (FEED) stage of mining projects found overruns in the 25–37% range, tracing them to ten recurring risk factors — among them unrealistic scheduling, inadequate feasibility studies, client pressure to minimise initial capital, cost estimates built on optimistic assumptions, and geotechnical or geological conditions that turned out less favourable than assumed.

None of that is a rounding error. A cost overrun in that range shows up as a visible share price reaction for a listed junior, and it compounds further if head grade or operating costs come in softer than the feasibility study assumed once the plant is actually running — a second, slower blow that lands after the market has already reacted to the first one, putting further pressure on the share price.

Set against that, a tightly scoped, genuinely independent check on the assumptions that matter most is a small number. The honest case for it isn't that a review guarantees a good outcome — it's that the alternative is finding out the same information later, at a point where it's categorically more expensive to act on, such as when the M&A team arrives to conduct the Due Diligence, or when commissioning is attempted. Trying to manage the information flow at that point becomes near impossible.

Sources: general infrastructure/industrial overrun figures (80% cost, 20% schedule) and the mining-specific figure (43% average overrun, four in five projects late/over budget) are both drawn from McKinsey's Metals and Mining insights, including "Getting Big Mining Projects Right: Lessons From (and For) the Industry." The FEED-stage overrun range (25–37%) and ten risk factors are drawn from Shafaay, Alqahtani, Alsharef & Chen, "Modeling construction cost overrun risks at the FEED stage for mining projects using PLS-SEM," Journal of Asian Architecture and Building Engineering, March 2025.