Buying or developing software: 10 buy vs. build criteria for making the right choice

The choice between buying standard software and developing custom software, or having it developed, is one of the most important decisions a CTO or IT manager can make. It is not only a matter of budget or functionality. It directly affects an organization’s strategic agility, ability to innovate, and operational effectiveness. A poor choice can still be felt years later in the form of high migration costs, rigid processes, or an IT environment that limits the business strategy instead of supporting it. So, what are the most important buy vs. build criteria for making the right choice?

When purchasing ready-made software, also known as commercial off-the-shelf software, or COTS, or simply “buy,” an organization pays through a license or subscription. Examples include platforms such as Salesforce, SAP, or Microsoft 365. “Build” refers to custom software development: software that is designed and developed specifically for an organization, either by an internal team or with the support of a specialized development partner such as NetRom Software.

Both options have advantages and disadvantages. Standard software offers speed, proven functionality, and maintenance provided by the vendor. Custom software offers full control, seamless integration with an existing IT landscape, and the ability to build exactly what an organization needs to differentiate itself from competitors. The challenge is determining which option delivers the most strategic value in a specific situation.

In this article, we discuss ten critical factors to consider when deciding between standard software and custom software. These factors serve as a strategic compass for making a well-informed choice between the two options.

1. Strategic advantage

The most important question is: do you want to gain a competitive advantage with this software? If the functionality directly contributes to what makes your organization unique in the market, custom software is almost always the better choice. With custom software, you can build exactly the processes or products that set you apart, without the unnecessary features that standard software packages inevitably include.

Generic business processes, such as financial administration, HR, and email management, are usually well suited for standard software. But as soon as IT plays a critical role in your business operations, for example in unique workflows or when multiple systems need to work together seamlessly, the advantage shifts toward custom software. With tailor-made software, you can create better integrations between systems, resulting in a more streamlined workflow and ultimately a stronger competitive position.

 A simple rule of thumb can help: use standard software for processes that every organization deals with. Use custom software to differentiate your organization. If you use the same COTS solution as your competitor, it becomes difficult to excel and gain a competitive advantage. 

2. Total Cost of Ownership (TCO)

The purchase price of a software package is only a fraction of the actual cost. To make a fair comparison, you need to look at the total cost of ownership, or TCO, over a period of at least five years, and preferably ten.

Standard software often seems less expensive at first. The initial costs are low, and you can be operational quickly. However, the costs can increase significantly over time. With SaaS services, you pay monthly subscription fees that increase as you add more users and/or consume more resources. In addition, business COTS packages are often priced per user per month. Add annual price increases, implementation costs, training, and any custom modifications, and the original cost advantage can quickly disappear. You also always pay for the full software package, including features you do not use.

Custom software requires a higher upfront investment. The development process includes several phases: analysis of business processes, design, development, testing, and fine-tuning after go-live. In return, you do not pay recurring license fees per user after delivery. The software is owned by your organization. Based on our project experience, the average payback period is between one and four years, because custom applications can optimize business processes and eliminate manual work. This leads to lower operational costs and ultimately a higher ROI. AI, in both assisted and agentic forms, also has an accelerating effect on this process.

When weighing standard software against custom software, it is important to make a realistic TCO calculation that includes all direct and indirect costs: from licenses and maintenance to the costs of process changes and missed efficiency gains.

3. Time-to-market

4. Functional fit

How well does the standard package align with your organization’s actual needs? An 80% fit may sound high, but the remaining 20% can affect the most business-critical processes. Standard software is developed for a broad group of users and is designed around common processes within specific industries. This inevitably means it includes features you do not need, which can result in an unnecessarily complex interface.

The pitfall with COTS is that organizations start adapting their processes to the software, rather than the other way around. Sometimes this is a sensible choice, but it can also come at the expense of operational efficiency. With custom software, you build only what you need, without unnecessary complexity. The software is aligned with your unique business processes and workflows, not the other way around.

6. Scalability and future readiness

Scalability starts with the question: will this software still fit the organization you want to be in three to five years? A fast-growing company has fundamentally different software requirements than a stable organization. Many companies logically start with a standard package: they can become operational quickly, and the investment is relatively low. But as the organization grows, companies begin to run into limitations. Standard software can quickly become a burden when processes become more complex, the number of users increases, and licensing costs rise accordingly. At that point, organizations start considering custom software, which often results in higher migration costs than if they had made that choice earlier.

Custom software can grow alongside your business. You can scale exactly in the direction you need, add functionality when it becomes relevant, and respond to current and future market opportunities. Custom software gives you the freedom to implement new features without being constrained by a vendor’s limitations.

8. Internal IT knowledge and development capacity

Building software requires more than just a development team. It involves architecture decisions, product management, cybersecurity expertise, and the willingness to provide long-term maintenance. Does your organization have that capacity in-house?

An honest assessment of internal maturity is essential. Knowledge retention should not be underestimated either: what happens if your best developers leave? With an external development team, for example through a nearshoring partner such as NetRom Software, you can mitigate that risk. You always have access to sufficient technical capacity, and knowledge transfer is structurally secured. If a developer leaves, the development partner provides a replacement and ensures a smooth handover.

9. Compliance, security, and data privacy

In highly regulated sectors, such as finance, healthcare, and government, compliance requirements can be decisive. Standard packages from major vendors often have extensive certifications, such as ISO 27001, NEN 7510, and SOC 2, and benefit from significant investments in security. At the same time, they offer less control over where data is stored and how it is processed.

There is another security aspect to consider: standard software can be an attractive target for cyberattacks. A vulnerability in the source code of a widely used COTS package can instantly make all organizations using that package vulnerable. With custom software, the attack surface is smaller and specific to your environment. However, this does require your own security strategy and sufficient knowledge to keep it up to date.

With custom software, you determine the security approach yourself. This starts with the choice of a potential development partner. European partners, for example, are generally required to comply with regulations such as the GDPR. But it is also reflected in the architecture. You define encryption according to your own requirements and decide where your business-critical data is stored, an issue that is becoming increasingly important in today’s geopolitical and regulatory landscape. Define in advance which compliance requirements are non-negotiable and include them in your decision.

10. Organizational readiness for change

Finally, there is a factor that may seem technical, but is not: how well can an organization deal with change? The implementation of standard software almost always involves process changes and resistance. You adapt the organization to the software, and that affects process efficiency.

Custom software adapts to the organization. However, this can also mean that inefficient processes are automated instead of improved. Include change management explicitly in your decision-making process, regardless of which type of software you choose.

The hidden factor: technical debt

One factor that is often overlooked in the buy vs. build decision is technical debt: the gradual accumulation of costs caused by technology choices over time.

In custom software, technical debt arises when quick fixes are chosen over sustainable architecture decisions, such as shortcuts in the code, deferred maintenance, or postponed migrations.

In standard software, technical debt is just as real. Consider organizations that use an outdated ERP package for years, where customizations and integrations have accumulated into a system that is difficult to untangle. A transition then becomes not only expensive, but also operationally risky.

It is advisable to explicitly include technical debt in your TCO calculation. For custom software development, define architecture standards and maintenance routines from day one, and choose an experienced development partner with proven ways of working that keep technical debt structurally manageable.

Your situation determines the right choice

There is no universally correct answer to the buy vs. build question. Use a structured approach to prevent the decision from being driven by habit, internal politics, or an enthusiastic sales pitch from a vendor.

Work through the ten factors systematically, quantify where possible, and involve both technical and business stakeholders. The best software decision aligns with your own organization’s strategy, capacity, and ambitions, not someone else’s. We are true believers in custom software. That is why we help organizations make the right choice.

Want to learn more about buy vs. build criteria?

Are you deciding between custom software and standard software? Or would you like to discuss these buy vs. build criteria in more detail? Feel free to contact us for a no-obligation conversation. Our motivated team is ready to discuss a smart custom software solution that aligns closely with your business objectives.