No board would accept the company’s taxes being done on a calculator with failing circuitry or flat batteries. Yet boards accept, without a moment’s reflection, decisions from a functional but quietly unmaintained mind. Most of us can recall such a situation, undiscussed or concealed, that ended badly. Perhaps nobody raised it for fear of intrusiveness, the whiff of tokenistic wellness, or optics. From what I observe, South African business culture is well placed to tame this exposure, precisely and practically.Judgments and decisions in finance, strategy, succession, and culture all depend on the cognitive composure of a handful of people. If we nurture everything except the minds doing the deciding, we are deep into lost value. Decisions are products of the mind: it is unwise to skip quality control. In our experience, the cause is seldom frank illness or dysfunction but situationally attributed: immensely capable people making consequential decisions under conditions not tolerated for a surgeon or pilot.Judgment under pressure is a measurable performance variable. It deteriorates in response to factors that are mostly ordinary and largely preventable. Sleep deprivation can impair cognitive performance to a degree comparable with blood-alcohol levels above the legal driving limit. Decision fatigue follows a predictable pattern: quality declines gradually, often disguised as a productive day packed with meetings. What appears to be a private matter of diary management can become a big determinant of outcomes that affect employees and shareholders alike.Overload rarely announces itself dramatically. It arrives long before burnout, narrowing thinking when a broader perspective is needed most. A director earning R200,000 a month may be operating at 30% effectiveness because they are working at 140% of their optimal capacity. High remuneration is often mistaken for strong performance long after the relationship has reversed.Professional sport treats cognition as an operational variable. Business still treats it as character: fixed and impenetrable to ordinary discussion. Committees are not minded, perhaps not equipped, to consider how the quality of thinking might be supported. That silence is a governance gap.Key-person risk is routinely insured against illness and accident, which is too low a bar for this discussion. The conditions that bring effort, composure and occasional brilliance to decisions are rarely discussed. Boards price currency exposure to the second decimal while carrying the unmitigated burden of an executive who slept four hours, 600km from home, arriving to resolve the transaction that will define the company’s decade.Newer research in high performance also upends old assumptions. In exceptional people, a history of trauma does not predict poor performance the way it does in the general population. Post-traumatic growth emerges as a predictor of the extraordinary. Genes linked to addiction proneness push towards extremes at both ends — severe underachievement or remarkable overachievement. We rightly treat the first. We now have the research and the techniques to cultivate the second.Now to why South Africa is well primed. King IV already demands effortful thinking about ethical leadership and the evaluation of committees and their members. In principle it suits the question well. In practice, boards hesitate to venture above the neck. They assess attendance, contribution and competence, but not the conditions under which judgment is actually being formed. A bakkie with five years of school runs is not prepared for overlanding in the Okavango.A board may legitimately ask the following practical questions, any one of which can uncover a real threat to decision quality:Is decision load visible? Someone should be able to say how many consequential calls the CEO is carrying and how, if at all, the calendar protects the largest of them. How were our highest-stakes decisions made? Not what was decided, but under what conditions: how much time, how late in the day, how far down the fatigue curve. After a major transaction, a structured afternoon review teaches more than a R200,000-a-head strategy retreat. What support exists, and is it safe to use? Internal structures are often distrusted and quietly avoided. A CEO should have private, frictionless, qualified support in place in ordinary times — not summoned in a crisis — so that clear reasoning is a habit rather than a rescue. And if support is visible, it should be described honestly: this is the care and refinement of the best, not the remedy of the fragile.Are the conditions of critical decisions governed? Predictably witless approvals happen at the end of 19-hour days. No morning vote should be put to a director who landed at OR Tambo at midnight. Is there a protocol for genuine impairment — and would it be accepted? It should be dignified, with routes and names agreed in advance, and it should apply to the chair as much as to the executive. Clumsy handling creates more entangled problems than the impairment itself.What is overstepping? A board is entitled to assurance, not access. Mandating support with no external option, demanding therapy notes or medical records, and compulsory psychological screening: these cross a line that is functional if not legal. You may no more look into a director’s private medical life than into his household bank statements. Push, and leaders retreat into a serious and sinister risk: concealment.How to begin? Make it a standing agenda item, once a year, treated as soberly as any other risk. And discourage status immunity: fatigue at the head of the table is as discussable as fatigue below it.We regulate the hours of pilots and doctors because we accept that their judgment needs replenishing. The same is true of the business mind. A board that prices every risk except the poise of its key people has not finished its work.• Dr Harris is a partner and private counsel at Harris Hawkins, a performance advisory practice. He advises boards and senior executives on the matters discussed in this article. Business Day