The People Due Diligence Gap: What the Data Room Will Never Tell You

Every acquisition in the UK mid-market has a financial due diligence workstream. Most have legal, commercial, and tax workstreams running in parallel. The advisers are credentialled. The reports are thorough. The fees are significant.

And yet the single largest category of post-completion value destruction in PE-backed acquisitions is not financial misstatement, not undisclosed litigation, not tax exposure. It is people. The management team that cannot deliver. The key person dependency that was invisible until it walked out. The employment liabilities that were technically in the data room but practically incomprehensible to anyone who was not specifically looking for them.

This is not a gap in the diligence process. It is a structural feature of how diligence is commissioned.

The Hierarchy of Diligence Attention

Financial due diligence has decades of methodology behind it. There are established firms, established frameworks, and established expectations about what a quality of earnings report should contain. Legal due diligence follows a similar pattern. The lawyers know where to look, what to ask for, and how to assess what they find.

People due diligence, by contrast, is either absent entirely, delegated to the legal workstream as an employment law compliance check, or conducted by generalist consultants who produce a document that reads impressively but tells the deal team almost nothing they can act on.

The employment law review will tell you whether contracts are compliant, whether there are outstanding tribunal claims, whether TUPE applies. These are necessary questions. They are also wildly insufficient as a basis for understanding the people risk in an acquisition.

What the employment law review will not tell you is whether the finance director is competent or merely present. Whether the sales team’s performance is a function of the product or of two individuals who are already being courted by competitors. Whether the HR policies in the handbook are actually followed or exist purely as a legal defence that has never been tested. Whether the culture that the management team described in the management presentation bears any resemblance to the culture that the workforce experiences.

These are the questions that determine whether a value creation plan is realistic. And in most mid-market transactions, nobody is asking them with any rigour.

Why the Data Room Is Structurally Misleading on People

A data room is an exercise in selective disclosure. This is not a criticism. It is a description. The vendor’s advisers populate it with documents that satisfy the diligence request list, and those documents are, by their nature, formal, backward-looking, and designed to present the business in a favourable light.

Employment contracts tell you what was agreed. They do not tell you what is actually happening. An organisation chart tells you who reports to whom on paper. It tells you nothing about where decisions are actually made, where the bottlenecks are, or which relationships are functional and which are quietly toxic. A staff turnover spreadsheet gives you a number. It does not tell you whether the people who left were the ones you would have wanted to keep.

The information that determines whether a management team can execute a value creation plan is almost never in the data room. It lives in the patterns of how decisions are made, how conflict is handled, how performance is managed, and how the leadership team responds under pressure. Accessing that information requires structured conversations, independent assessment, and a framework for interpreting what you find. It requires, in other words, a dedicated people due diligence workstream run by people who have seen enough portfolio companies to recognise the patterns.

The information that determines whether a management team can execute a value creation plan is almost never in the data room. It lives in the patterns of how decisions are made and how the team responds under pressure.

The Management Presentation Problem

In most mid-market deals, the buyer’s primary exposure to the management team before completion is the management presentation. This is a carefully rehearsed performance in which the leadership team presents the business at its best, answers prepared questions with prepared answers, and projects an impression of competence and alignment.

The management presentation is the talent equivalent of a show flat. It tells you what the space could look like under ideal conditions. It tells you nothing about the plumbing.

Sophisticated buyers supplement the management presentation with individual management interviews, often conducted by the deal team or by an operating partner. These conversations are better than nothing. They are also structurally limited by the fact that the people being assessed know they are being assessed, the assessors are often generalists making judgements in domains where they lack specific expertise, and the entire process takes place within the artificial context of a transaction where everyone is on their best behaviour.

A structured people due diligence process does something different. It assesses the management team against the specific requirements of the value creation plan, not against a generic competency framework. It identifies the gaps between what the plan requires and what the current team can deliver. It quantifies, as far as possible, the cost of closing those gaps, whether through development, recruitment, or managed exits. And it does this with the independence and pattern recognition that comes from having done it across dozens of transactions rather than relying on the deal team’s instinct.

What a Proper People Due Diligence Actually Covers

The scope of a genuine people due diligence extends well beyond the employment law compliance check that most deals settle for. At minimum, it should address the following.

Leadership capability against plan requirements. Not whether the management team is competent in the abstract, but whether they have the specific skills, experience, and temperament to deliver what the value creation plan demands over the hold period.

Key person dependency mapping. Identifying the individuals whose departure would materially affect the business, understanding what binds them to the organisation currently, and assessing the likelihood and cost of their departure post-completion.

Employment liability quantification. Going beyond the legal compliance check to model the realistic cost of the employment liabilities that will need to be addressed post-completion, including restructuring costs, settlement agreements for underperforming seniors, and the cost of upgrading roles that are currently filled by people who are wrong for the next phase.

Cultural assessment. Understanding how the organisation actually operates, as distinct from how it is described. This is particularly critical in founder-led businesses where the culture is often a direct extension of the founder’s personality, and where the founder’s departure or reduced involvement post-deal will change the operating environment in ways that are difficult to predict without structured assessment.

HR infrastructure readiness. Assessing whether the HR function, policies, systems, and processes are adequate for a PE-backed operating environment, or whether significant investment will be required post-completion to bring them to the standard the value creation plan assumes. An HR MOT conducted as part of the due diligence process provides a structured assessment of this readiness.

The Cost of Not Doing It

Consider a mid-market acquisition at £15m enterprise value. The deal team budgets £300,000 for financial due diligence, £150,000 for legal, £75,000 for commercial. People due diligence, if it exists at all, sits within the legal workstream at an incremental cost of perhaps £15,000 for an employment law compliance review.

Now model what happens when the people risks that were not assessed materialise in the first eighteen months post-completion.

Assume the value creation plan requires a new commercial director. The incumbent is not removed until month four because nobody assessed them properly before completion. Recruitment takes four months. The new hire takes six months to reach full effectiveness. That is fourteen months of sub-optimal commercial leadership in a business that was acquired on the basis of a plan that assumed the right team would be in place from day one. The direct cost of the recruitment and the settlement for the departing incumbent might be £120,000. The indirect cost of fourteen months of lost commercial momentum is a multiple of that.

Assume two of the five people identified post-completion as key person dependencies leave within the first year. They were not identified pre-deal because nobody conducted a structured assessment. Their departure triggers client losses, knowledge drain, and six months of management distraction. Conservative cost: £200,000 to £400,000 in direct and indirect impact.

Assume the HR function, which looked adequate on paper, turns out to have significant compliance gaps that require immediate remediation. Contracts are non-compliant with current legislation. The disciplinary process has not been followed consistently, creating tribunal exposure. The data protection arrangements are inadequate. Remediation cost: £40,000 to £80,000, plus the management time to oversee it.

Total people-related costs in this scenario: somewhere between £360,000 and £600,000 in the first eighteen months. Against a £15m enterprise value acquisition, that is two to four percent of the purchase price, consumed by risks that a £30,000 to £50,000 people due diligence workstream would have identified, quantified, and in many cases mitigated before completion.

The arithmetic is not subtle. The fact that it is routinely ignored tells you something important about how deeply the hierarchy of diligence attention is embedded in deal culture.

The Uncomfortable Conclusion

Financial due diligence exists because PE firms learned, decades ago, that acquiring a business without understanding its financial reality was reckless. Legal due diligence exists for the same reason. People due diligence barely exists because the industry has not yet internalised the equivalent lesson about people risk, despite the evidence that people-related issues are the most common source of post-completion value destruction in the mid-market.

The firms that have learned this lesson are not the ones with the most sophisticated financial models. They are the ones that have lived through enough post-completion crises to recognise that the risks they failed to assess before the deal were, in retrospect, entirely assessable. They just were not looking. Our financial due diligence article explores the customer dimension of this same problem.

The data room will show you the contracts, the org chart, and the turnover numbers. It will never show you the management team’s actual capability, the key person dependencies that will determine whether the plan survives contact with reality, or the cultural dynamics that will shape every decision for the next four years. Those things require a different kind of assessment, conducted by people who know what they are looking for.

The question is not whether you can afford to do it. It is whether you can afford, again, not to.

---

If you are preparing for a transaction and want to understand the people risk before completion rather than after it, talk to us. Our private equity people consultancy team conducts structured people due diligence for PE firms and corporate acquirers across the UK mid-market.