Build vs. Buy MES: Why Partnering With Experts Beats Building In-House

Modern manufacturers face a pivotal choice when they need a Manufacturing Execution System (MES): build software internally or buy a proven platform. The build option can feel attractive. It promises a perfect fit, total control, and the sense that you are investing in your own intellectual property. The buy option can feel less glamorous, but it offers speed, predictability, and the ability to stand on the shoulders of domain experts.

This decision has real consequences for growth, margins, and risk. In aerospace, EVs, robotics, and other advanced manufacturing, the clock is always ticking. Certification requirements evolve, supply chains shift, product designs change weekly, and operations expand from one site to many. Long-term success stems from focusing scarce engineering time on the product and the factory, rather than reinventing complex software that a specialist vendor already maintains, secures, and scales.

The goal of this article is to help business leaders evaluate the trade-offs clearly and make a decision that supports both near-term execution and long-term competitiveness.

The Allure of Building an MES

There are good reasons leaders consider building. Customization promises an exact fit to your processes. Ownership promises independence from vendor roadmaps. Internally built tools can also become a source of pride for teams that have invested years in them.

Unfortunately, the perceived benefits often rest on two assumptions that do not hold up in practice:

1. The assumption that an internal build will be cheaper, at least at the start.
   
   
2. The assumption is that a one-time investment produces a stable tool that will not demand significant ongoing attention.
   
   

Software does not stand still. As your products, processes, and teams evolve, the system that orchestrates production must evolve too—the effort to keep a custom MES current compounds every year.

Hidden Costs of Building Your Own MES

Development time and opportunity cost

An enterprise-grade MES requires specialized talent across backend services, UI, data modeling, industrial connectivity, security, and compliance. Recruiting those skills is expensive. Retaining them is more costly. Even if you can staff the team, every sprint spent on internal MES features is a sprint not spent on the core product, new lines, or new markets.

Large software programs also carry material schedule and budget risk. Independent research by McKinsey found that large IT projects run 45% over budget and 7% over schedule, while delivering 56% less value than predicted. Long-running datasets show low success rates; for example, the Standish Group’s CHAOS 2020 results report 31% successful, 50% challenged, and 19% failed projects (SAGE journal citing CHAOS 2020). These numbers are not MES-specific, but MES programs are complex, integration-heavy, and multi-year, which places them squarely in the risk profile.

Infrastructure, performance, and uptime

Owning an MES means owning the stack. That includes cloud architecture, database scaling, performance tuning, monitoring, disaster recovery, and uptime commitments to your internal stakeholders. Each element needs design, implementation, and continuous care. Skimping on any part invites degradations that ripple into production lines and supplier coordination.

Security and compliance exposure

Manufacturers handle controlled technical data, supplier records, and increasingly sensitive operational telemetry. Security is not a bolt-on. Patching, penetration testing, identity and access management, and incident response must be ongoing. According to IBM’s Cost of a Data Breach 2024 report, the global average cost reached USD 4.88 million .

Compliance adds more weight. If you work in aerospace or defense, you are contending with frameworks such as AS9100, ITAR, and NIST 800-171. An internal build must prove it can enforce process controls and maintain auditable records across engineering changes, approvals, and genealogy. That is not a small lift.

Long-term scalability and integration

Scaling from a single site to a multi-site network, from dozens to thousands of work orders per day, and from a few systems to a broad ecosystem requires careful architecture. Successful MES platforms anticipate this journey with multi-tenant patterns, environment isolation, efficient data pipelines, and stable APIs. Custom projects often begin as tactical tools for a single program, only to later discover the architectural gaps that make scaling them painful and expensive.

The integration footprint is another source of surprise. MES must connect to ERP, PLM, QMS, test systems, equipment data sources, supplier portals, analytics, and more. Every integration you build, you own. Every time an upstream system changes, your team pays the tax again.

The Strategic Disadvantage of Maintaining In-House Software

Talent distraction

Your most valuable engineering leaders should be accelerating product cycles, architecting scalable production systems, and unlocking new value for customers. When they become the custodians of a custom MES, they become a software vendor to the rest of the company. That shift in accountability limits their ability to drive innovations that differentiate your business.

Slower time to value

Markets do not wait. When internal teams must design, build, test, and roll out core MES capabilities before the next program can begin, the program is delayed. Competitors who adopt proven software get moving sooner. They can focus on standardizing work, raising first-time-right rates, and flowing data across the enterprise instead of planning foundational features.

The risk of technical debt and key-person dependency

Even well-run internal programs accumulate debt. Over time, changes in personnel and priorities leave rough edges, undocumented constraints, and fragile integrations. The question becomes unavoidable: what happens when your best developer leaves or the budget tightens and that long-promised refactor slips again?

The Benefits of Buying a Proven MES Platform

Lower and clearer total cost of ownership

A subscription model converts variable, hard-to-predict internal spend into a known operating expense. You do not need to budget separately for application infrastructure, database operations, monitoring stacks, backups, or disaster recovery drills. Vendors also pool investments across customers, so your effective cost per capability is lower than what you can achieve alone at a similar quality.

Faster implementation and iteration

A modern MES comes with prebuilt workflows for work orders, routing, work instructions, traceability, nonconformances, approvals, and analytics. You configure rather than code. That means early value in weeks, rather than years, followed by an incremental rollout across lines and sites. Short feedback loops enable operations teams to standardize faster and eliminate sources of error.

Continuous improvement without hidden maintenance

With a vendor, updates are part of the service. New features, usability improvements, extensibility, and performance enhancements arrive regularly. Your team benefits from patterns the vendor has already solved at other plants and programs, along with hardening that comes from operating at scale. Your engineers stay focused on manufacturing excellence rather than patch cycles.

Industry expertise baked into the product

An MES vendor who works across aerospace, EVs, robotics, and other advanced sectors internalizes best practices about compliance, change management, and scale. LNS Research’s MESA/MOM “Metrics that Matter” (2013 cohort) reported 22% average annual improvement in on-time & complete shipments for MES users and 19.4% improvement in net profit margins for MOM-suite users (LNS Research, 2014). Although the exact lift varies by industry and maturity, the directional impact is consistent: disciplined, data-driven operations outperform ad hoc tools.

MES for Enterprise Manufacturers

Enterprise manufacturing brings unique demands that amplify the build-versus-buy calculus.

Multi-site orchestration. Enterprises must coordinate standardized processes across plants, suppliers, and contract manufacturers to ensure seamless operations. A suitable MES manages shared templates with local flexibility, ensures consistent approvals and sign-offs, and centralizes traceability and genealogy.

Integration at scale. You likely run a portfolio of systems: ERP for finance and supply chain, PLM for product definition, QMS for corrective actions, data historians, and test systems for equipment and product signals. An enterprise-ready MES ships with stable APIs and prebuilt connectors that make data movement a configuration task rather than another development project.

Performance and reliability at high volume. A global plant network demands low latency across sites, resilient data pipelines, and the ability to sustain spikes during ramp or engineering change. Vendors engineer for these conditions every day, which reduces the risk that your internal team becomes a bottleneck.

Governance and compliance. Auditors expect end-to-end records for the manufacturing process: who did what, when, with which parts and revisions, under which approvals. An MES designed for regulated industries can enforce these controls out of the box and maintain immutable records.

Hidden Risks of Upkeep That Do Not Show Up in the Initial Plan

Even capable internal teams misjudge how much ongoing attention a custom MES requires. Consider these categories of maintenance that can compound over time:

Security and privacy. Threat models evolve. You need regular security reviews, dependency updates, encryption practices, and identity controls. The cost of falling behind is not theoretical. As noted in IBM’s Cost of a Data Breach 2024 report, the global average is USD 4.88 million; that figure excludes downstream impacts like lost contracts or program delays .

Vendor churn in your stack. Cloud providers deprecate services, libraries age out, and browsers change behavior. Each shift creates work. Product teams doing feature work usually win the prioritization battle, which means the platform spend you avoided at the start becomes an unplanned emergency later.

Operational toil. On-call rotations, runbooks, performance investigations, and integration breakages consume time. When an ERP upgrade changes a field or a PLM integration needs a new version, someone has to test and deploy the fix.

Scaling surprises. What seemed fine at one site can buckle at five times the pressure. Analytics that worked for thousands of records may not work for hundreds of millions. Without deep database and distributed systems expertise, teams underestimate the work required to preserve responsiveness and reliability at scale.

The Strategic Advantage of Partnering Instead of Building

When a manufacturer buys a proven MES, the vendor takes ownership of infrastructure, server costs, updates, and integrations. Your teams regain focus on product and process innovation. Instead of building commodity capabilities, they:

• Introduce new lines faster because core workflows are ready to configure.
  
  
• Capture as-built traceability consistently, which simplifies audits and speeds corrective actions.
  
  
• Leverage prebuilt analytics to see bottlenecks and quality drift early.
  
  
• Evolve processes confidently, knowing that upgrades will keep pace with evolving standards and customer requirements.
  
  

Independent studies show frequent overruns and under-delivery—for example, McKinsey found 52% private sector IT projects see overruns; with 17% being “Black Swans” exceed budget by 200%–400%. By contrast, established MES platforms spread the cost of innovation across many customers and convert operational lessons from one domain into product improvements that benefit all.

Why Partner With First Resonance

First Resonance builds ION, a modern MES designed for advanced manufacturers who need to move quickly without compromising on quality or compliance. We work with leaders in space, energy, defense technology, and other high-growth sectors that must iterate hardware rapidly while maintaining rigorous standards.

What sets ION apart for business leaders:

A platform that manages the heavy lifting. ION operates the infrastructure, data stores, and monitoring, ensuring your teams don't have to. Our updates arrive continuously, and your operations benefit from performance and reliability investments that reflect the needs of data-intensive factories.

Built-in best practices. ION ships with manufacturing workflows that support work orders, work instructions, approvals, nonconformances, and change management. These are shaped by real-world usage across aerospace, EVs, robotics, and other complex environments.

Integration and openness. ION is API-first and designed to connect with ERP, PLM, QMS, test systems, and analytics. That means data flows where it should, without fragile one-off scripts.

Proven outcomes. Public case studies show how manufacturers have used ION to scale production and improve engineering productivity. Examples include space and defense companies that improved traceability and saved measurable engineering time per week, and satellite manufacturers that accelerated development while growing revenue.

A partner mindset. We engage as collaborators. That means helping you align processes to industry benchmarks, sharing implementation patterns that work across plants, and continually investing so the platform grows with you.

Benefits of Partnering With a Proven MES Vendor

To summarize the advantages of a vendor partnership for executives evaluating total cost and strategic focus:

• Predictable economics. A subscription model clarifies spend. You avoid surprise rebuilds and redistribution of staff from core programs to platform maintenance.
  
  
• Time to value. Prebuilt capabilities enable you to support a program now and then expand incrementally. Faster time to stabilization means earlier measurable impact on throughput and quality.
  
  
• Continuous innovation. You benefit from the vendor’s product roadmap, including performance improvements, usability refinements, and new AI-driven capabilities that you do not have to fund alone.
  
  
• Operational resilience. Dedicated reliability investments and shared learnings strengthen the platform for every customer.
  
  
• Focus on differentiators. Your teams can direct their energy to product, production system design, supply chain orchestration, and customer outcomes, not the plumbing beneath them. 

A Practical Evaluation Framework for Decision-Makers

If you are weighing options, use the following questions to guide a structured choice:

1. What is the earliest date the next program or facility needs full MES support? If the answer is months, not years, buying is the only realistic path.
   
   
2. What is the all-in cost of an internal build over five years? Include cloud costs, security, compliance audits, integration upkeep, and the cost of attrition.
   
   
3. Where do we want our best engineers focused? If your competitive advantage comes from rapid product iteration and factory agility, do not make them a software vendor of internal tools.
   
   
4. What audit, certification, or traceability requirements do we face? Choose the option that makes these requirements easier to meet across sites.
   
   
5. How will we scale to more lines and facilities? Favor a platform with proven multi-site patterns and a clear integration story.
   
   

Conclusion: Choosing Growth Over Internal Tools

Building a custom MES can feel empowering. It promises a perfect fit and independence. In reality, the hidden costs, maintenance burden, security and compliance exposure, and long-term scaling demands make internal builds a risky path for most manufacturers. The data on large software programs is sobering, as can be seen in McKinsey’s analysis of 5,400 IT projects (2012): 45% over budget, 7% over schedule, and 56% less value than predicted.

Buying a proven MES aligns budgets, speeds implementation, and gives your teams a strategic advantage. It lets you redirect scarce engineering talent toward the work that wins markets: faster iteration, higher first-time-right, reliable deliveries, and the ability to scale without chaos. That is why partnering with a specialist is not just a software decision. It is a business growth decision.

Call to Action

Learn how First Resonance helps manufacturers scale without the burden of building and maintaining their own MES. If you are assessing build versus buy for an upcoming program or site, talk with our team about ION and see how a modern MES can accelerate your roadmap while reducing risk.

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