The median EBITDA underperformance versus the acquisition business plan at PE-backed companies by the end of Year 2 post-close. Not a catastrophic miss. Not a thesis-killing outcome. Just a quiet, consistent, systematic gap between what the model said would happen and what the business actually produced — in the period when the model mattered most.
Harvard Business School · PE acquisition business plan performance study · 2024The miss is not random. Five structural patterns account for the overwhelming majority of Year 1 shortfalls — and every one of them leaves evidence in the data room, the CIM, and the normalized financials long before the deal closes.
The LBO model is a deterministic machine. You enter assumptions — revenue growth, margin expansion, entry multiple, exit multiple, leverage ratio, hold period — and it returns an IRR. Change the assumptions and the IRR changes. The machine is perfectly logical. The problem is that the assumptions are almost always wrong, in the same direction, for the same reasons, deal after deal after decade after decade.
The 28% median EBITDA miss is not a story about bad deals or bad sponsors. It is a story about structural optimism baked into the acquisition process itself — optimism that is not dishonest, not uninformed, and not correctable by hiring smarter analysts. It is optimism that is generated by the incentive architecture of the deal process: sellers who present the best version of their financials, advisors whose fees are contingent on close, and buyers who have invested weeks of partner time and are psychologically committed to a deal by the time they are stress-testing assumptions.
Five patterns show up in the data with consistency. They are not equally weighted in every deal, but at least three of the five are present in the majority of cases where Year 1 EBITDA materially underperforms the acquisition plan. Here is what they look like, where they hide, and how to find them before you are twelve months post-close wondering what happened to your base case.
The normalization that went one turn too far EBITDA normalization is necessary and legitimate. Owner compensation above market, one-time legal expenses, non-recurring restructuring costs — these are real adjustments that reflect the business's true earnings power under new ownership. The problem is the adjustments that are real in isolation but aggressive in aggregate. Each one is individually defensible. Together they produce a normalized EBITDA that is 15–25% above reported EBITDA — and a run-rate that the business cannot achieve in Year 1 without the cost reductions and operational improvements that are already in the value creation plan. The normalization and the value creation plan are doing double work on the same dollar of EBITDA. When the value creation initiatives slip by six months — and they almost always slip by six months — the normalized EBITDA base is exposed as aspirational.
Integration costs that weren't in the model The acquisition model has a line for integration costs. It is almost always too small, too early, and too narrowly defined. System migrations take 18 months, not 6. Management time lost to integration activities — ERP implementation, HR policy harmonization, benefits consolidation, brand transition — does not appear as a cost in the income statement, but it appears as a drag on EBITDA as the management team stops selling and starts administering. The integration costs that kill Year 1 performance are not the ones in the model. They are the opportunity costs of management attention redirected away from the revenue-generating activities that the acquisition thesis assumed would continue uninterrupted.
The customer that doesn't survive the ownership transition Customer concentration is disclosed in the CIM. It is almost never modeled correctly. A business where Customer A represents 28% of revenue is flagged in every IC memo written. The risk is acknowledged. What is not modeled is the specific probability that Customer A — who has a 12-year relationship with the founder who just sold the business and is now on a two-year earnout — will reduce their spend, pause expansion, or request contract renegotiation in the twelve months following close. The relationship was with the person, not the company. The model assumed the revenue was with the company.
The management team that built the business to $10M EBITDA Operators who built a business to $10M EBITDA are excellent at a specific set of things: selling, building product, managing a team of 50, and running a business where the CEO knows every customer personally. They are often not excellent at the things a PE-owned $30M EBITDA business requires: sophisticated financial reporting, debt covenant management, board-level communication, and operating a business where the CEO has to trust functional leaders they did not personally hire. The gap between what the management team is excellent at and what the PE ownership model requires is a Year 1 operational drag that appears in EBITDA as G&A creep, missed sales targets, and leadership team turnover.
The 100-day plan that nobody followed The 100-day plan is produced before close, reviewed at the IC meeting, and filed in the deal room. In the majority of LBOs, a meaningful portion of the 100-day plan's value creation initiatives are twelve months behind schedule by the time the first-year EBITDA is reported. Not because the initiatives were bad ideas. Because the 100-day plan was built in a room by a deal team and a consultant, and the management team who had to execute it was finishing a transaction while running a business. The plan assumed Day 1 readiness that does not exist at any company that has just been through a six-month sale process.
The patterns do not operate independently. They interact. A normalization that assumed $500K in owner compensation add-back lands in a Year 1 budget that was already stretched by $300K in integration costs that were not in the model. The management team, distracted by integration, misses Q2 sales targets. The customer who had a twelve-year relationship with the founder quietly rebids their contract to a competitor. By Q3, three of the five patterns are simultaneously expressing in the income statement, and the deal team is building a revised EBITDA bridge for the next board meeting.
The 28% median miss is not one bad assumption. It is the compounding of several moderately optimistic assumptions that individually survived IC scrutiny and collectively produced a Year 1 reality that the model never contemplated.
“The patterns that produce Year 1 EBITDA misses are not hidden. They are visible in the normalized financials, the customer revenue schedule, the management team assessment, and the integration plan — before close. The question is whether the underwriting process is designed to surface them.”
Each of the five patterns leaves a specific evidence trail in the pre-close diligence materials. The normalization review surfaces Pattern 1. The integration plan assessment surfaces Pattern 2. The customer revenue schedule, churn history, and contractual structure surface Pattern 3. The management team reference calls and organizational chart surface Pattern 4. The 100-day plan feasibility assessment — specifically, the question of which initiatives require management bandwidth that is simultaneously consumed by integration — surfaces Pattern 5.
What the traditional IC process is less good at is weighting these risks correctly, assigning probability estimates to the scenarios, and building a base case that reflects the actual expected outcome rather than the management presentation's best case. The analyst who writes the IC memo has the same information. What they are doing with it — selectively, under career-incentive pressure — is a different question.
A structured risk engine that is explicitly designed to look for the five patterns — that asks whether normalized EBITDA is double-counting value creation upside, whether the customer revenue schedule shows concentration risk that is not modeled in the downside case, whether the 100-day plan timeline is feasible given management bandwidth assumptions — catches what the IC memo glosses over.
The 28% median underperformance is measured at the company level against the sponsor's acquisition business plan, not against public benchmarks. It controls for market environment — the miss is present across economic cycles, suggesting it is structural rather than macro-driven. At the deal level, roughly 35% of buyouts outperform their acquisition plan in Year 2. The distribution is wide. The median, however, is consistently negative across sponsor tiers, company sizes, and sectors. The optimism is systemic, not idiosyncratic.
“The acquisition model should not ask: 'What is the IRR if the management presentation is accurate?' It should ask: 'What is the IRR when these five patterns express, in combination, in Year 1?' The answer to the second question is the real return profile of the deal.”
Dealithic's risk engine explicitly models all five Year-One miss patterns — before you write the check.
Upload the CIM. Our agent pipeline runs normalization review, customer concentration scoring, management assessment, integration cost modeling, and 100-day plan feasibility — and returns a conviction score that reflects the actual expected outcome, not the seller's best case. Start free.
Run a Deal Free →“The Year 1 miss is not a surprise to anyone who looked at the right data with the right framework before close. It is a surprise only to the deal team that was looking at the management presentation through the lens of the model they wanted to build.”
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