Most engineering leaders can tell you exactly what they spend on developers, tooling, and infrastructure. Far fewer can tell you what they spend on building the wrong thing.
That gap is where the real money goes.
The Hidden Cost Nobody Budgets For
Rework is the largest unbudgeted line item in most engineering organisations. Industry data puts it at between 26% and 40% of all development effort, and the Standish Group's CHAOS reports attribute 80% of software project failures to requirement-related issues rather than technical ones. IBM's Systems Sciences Institute traced 60% of rework costs directly to incorrect or incomplete requirements.
Put simply: the bottleneck is not the code. It is the shared understanding of the domain before the code gets written.
For a team of 20 engineers at an average fully-loaded cost of €80,000 per year, that translates to roughly €250,000 in annual rework attributable to requirements misalignment alone. Most organisations absorb this as normal. It is not normal. It is an unrecoverable loss.
What Domain-Driven Design Training Actually Changes
Domain-Driven Design addresses this at the source. Rather than treating requirements as a handover artefact passed from business to engineering, DDD establishes a shared modelling practice: a common language, a common representation of the domain, and a set of tools for making business complexity legible to technical teams and technical decisions legible to business stakeholders.
The downstream effects show up in three places.
Discovery speed. Dan Kantic of Maurer Electronics, who attended the EventStorming workshop at DDD Academy in 2025, put it directly: this workskshop "significantly shortened the discovery phase." EventStorming, developed by Alberto Brandolini, compresses weeks of requirements gathering into a single collaborative session. Business and engineering teams model the domain together on a shared wall, surfacing conflicts and blind spots before they become defects.
Architectural confidence. Sébastien Van De Poel of Arcrit, following the Leadership in Software Design workshop, described a lasting shift: "I now have more confidence in my code and in my architectural choices. It also helped me coach others better, because I can clearly explain why certain choices are better than others in specific situations, instead of relying on personal preference or habits."
Brownfield modernisation. For teams managing legacy systems, DDD provides a concrete path through the complexity. Stijn Nel of OnCore noted that techniques like the Modularisation Maturity Index and Context Mapping gave his team "additional tools for assessing existing systems and supporting better estimations and modernisation roadmaps." The work of understanding the domain feeds directly into the work of decomposing a monolith or rationalising a sprawling microservices landscape.
What the Research Confirms
The 2024 DORA Accelerate State of DevOps Report, drawing on data from over 39,000 professionals globally, identifies clearly defined team boundaries and shared domain understanding as consistent predictors of high delivery performance. Teams with strong boundaries deploy more frequently, recover from failures faster, and report lower burnout.
Carnegie Mellon research puts a number on the return: every euro invested in improving requirements processes returns between €3.30 and €7.50 in reduced maintenance costs and rework. DDD training is precisely this kind of investment.
The Compounding Effect
One aspect of DDD training that does not show up in ROI calculations but matters enormously in practice is the coaching effect. Engineers who attend leave with not just new techniques but a framework for explaining their decisions to colleagues, to business stakeholders, and to incoming team members.
Vojtech Bartos, who attended the EventStorming Masterclass with Alberto Brandolini, described using the method repeatedly with clients since 2020: "I invite developers and clients and together we map out the processes that will be digitised on the wall. The developers praise the better understanding of the overall scope."
That kind of multiplier, one trained engineer bringing the practice into multiple client engagements, is what separates a training cost from a capability investment.
The Decision for Engineering Leaders
The question is not whether DDD training delivers a return. The data from industry research and from practitioners in the field is consistent on this point. The question is whether your organisation is currently absorbing the cost of not having it, quietly, through rework, slow discovery, and architectural decisions that become expensive to reverse.
What will be your decision?
This blog post draws on data from the DORA 2024 Accelerate Report, the CISQ Cost of Poor Software Quality report (2022), Carnegie Mellon SEI research, IBM Systems Sciences Institute, and the Standish Group CHAOS Report, alongside firsthand testimonials from DDD Academy participants across Belgium, Germany, Denmark, and the Netherlands.