Apps and software

Modernising software: mistakes to avoid before changing your system

The program is still working, but every change requires workarounds, data is duplicated, and part of the team keeps parallel tasks in spreadsheets, emails or messages. At that point, modernising software may seem like an obvious decision. The challenge lies in deciding what to retain, what to change and which problem should be addressed first.

This article will help you recognise the mistakes that most compromise a modernisation project. By the end, you will be able to review your situation more effectively and decide whether you need to adjust the current system, replace one part of it or consider a new solution.

What you are trying to achieve when modernising software

The aim should not be to have a more up-to-date tool, but to improve a specific operation. This may involve reducing manual steps, accessing information without relying on multiple sources, preventing data-entry errors, or giving customers and the team clearer access to certain processes.

Before discussing technology, separate three levels:

Objective: what should change in your business or for the people who use the system.
Scope: which processes, data, users and rules need to be included to achieve that change.
Solution: how it will be delivered, whether through an improvement to the current software, an integration, an off-the-shelf tool or bespoke development.

This distinction prevents you from starting with a fixed answer—for example, “we need a new app”—before the problem has been properly defined.

Common mistakes when modernising software

1. Starting with technology rather than the process

Symptom: the conversation quickly focuses on changing platforms, redesigning screens or adding features, but it is unclear which task is failing or who performs it.

Cause: the visible ageing of the program is mistaken for the operational cause. An outdated interface may be inconvenient, but it may also conceal a process with unnecessary steps, poorly defined rules or responsibilities allocated without clear criteria.

Consequence: you may transfer the same problem to a new system. The team will have to adapt to another tool without delays, incomplete data or duplication being eliminated.

Correction: first describe the actual flow of a relevant task. State who starts the action, what information they need, which decisions they make, where exceptions occur and how the process ends. You can then assess which part needs to change and which only requires a targeted improvement.

2. Trying to replace everything at once

Symptom: the project brings together every outstanding need: customer management, orders, documents, reports, permissions, automation and new integrations.

Cause: modernisation is used as an opportunity to try to solve every accumulated problem. This is understandable, but treating every request as a priority makes it impossible to distinguish what is necessary from what can wait.

Consequence: the scope becomes difficult to validate. It also increases the risk that important decisions remain unresolved until later stages, when changing one feature affects other parts of the system.

Correction: classify each need into four groups: essential for the first version, desirable, future or out of scope. For each feature, ask which objective it supports, who will use it, what will happen if it is postponed and how you will verify that it works.

3. Taking data migration for granted

Symptom: people talk about “moving the information” to the new system without an inventory or criteria for determining which data is still useful.

Cause: migration is treated as an automatic technical task. However, data may be spread across programs, files, different formats or incomplete records.

Consequence: you may transfer duplicated, outdated or difficult-to-interpret information. Questions may also arise about fields, histories, associated documents and owners once the change is already under way.

Correction: prepare an inventory before choosing the solution. Identify the source of each item of data, its format, its owner, its current use and whether it should be retained, corrected, archived or discarded. Also define what must be checked before the migration can be considered valid.

4. Ignoring the people who use the software every day

Symptom: the system is decided on based on a general management need, but the people who enter, consult or correct information have not taken part in defining it.

Cause: it is assumed that everyone uses the program in the same way. In practice, an administrative staff member, an operations manager and an external user may need different permissions, data and workflows.

Consequence: the tool may look right on paper and still lead to informal workarounds. Notes, messages and parallel files return because the intended flow does not fit the real work.

Correction: identify user profiles and specific tasks. It is not enough to say “internal team” or “customers”. Define what each profile can view, create, modify or approve, as well as the cases in which they need help or an alternative.

5. Integrating tools without defining the information flow

Symptom: a request is made to connect the new software with billing, email, inventory or another platform, but it is not specified which data moves, in which direction or what happens if the connection fails.

Cause: an integration is understood as a simple link between two tools. In reality, you need to decide which system holds the primary data, when it is updated, which rules apply and how errors are detected.

Consequence: you may create inconsistent information across systems or depend on manual processes to resolve incidents. In addition, an integration may affect scope and maintenance more than expected.

Correction: document each connection using simple questions: which system sends the information, which receives it, which fields are involved, when they are synchronised and who reviews an incident. If an external tool imposes limits or changes its terms, it is advisable to validate this before making a technical decision.

6. Not defining what it means for a feature to be complete

Symptom: requirements are expressed using words such as “intuitive”, “complete”, “fast” or “easy to use”, without a specific situation that makes them verifiable.

Cause: acceptance criteria are missing: observable conditions that indicate whether a feature meets what was agreed.

Consequence: reviews are based on different impressions. What you considered included may be interpreted as a later improvement, and a feature that appears complete may fail to cover errors, permissions or exceptional cases.

Correction: turn each relevant requirement into a check. For example, in a hypothetical case: “when an authorised person records an order with all mandatory fields, the system displays a confirmation and makes the order available to the profile responsible for managing it”. Add what should happen if information is missing or if the user does not have permission.

7. Forgetting who will maintain the system afterwards

Symptom: the conversation focuses on launch, but not on updates, access, documentation, incidents or future changes.

Cause: modernisation is seen as a closed delivery. However, software is part of an operation that may change: new services, roles, rules or external tools may emerge.

Consequence: a small modification may become an uncertain decision because no one knows what depends on what, who retains access or how to update information without affecting operations.

Correction: define from the outset who will administer the system, which people need training, what documentation should exist and what types of changes you anticipate. It is also advisable to clarify ownership and control of accounts, data and third-party services.

How to prevent these mistakes before deciding

You do not need to have the solution resolved in order to prepare a modernisation properly. You do need to make visible the decisions that can alter the scope.

Start with a process that has a clear impact on your activity. Bring together the people who know it and describe the starting point, the points of friction and the expected outcome. Then separate what you know from what you still need to validate.

In particular, do not consider these aspects closed:

the information that must be retained and its actual state;
the profiles that will use the system and their permissions;
the process rules, exceptions and approvals;
the tools that need to be connected;
the elements that are part of a first version and those that can wait;
how you will verify that each feature addresses the defined need;
responsibility for maintenance, content, accounts and access.

This preparation does not eliminate all uncertainty. It makes uncertainty explicit so that it can be addressed before it becomes a development problem.

Software modernisation review checklist

Use this list before approving a replacement, an improvement or a new solution:

If you cannot answer several of these points, it does not mean you should stop the entire initiative. It means it is advisable to narrow the uncertainty first before committing to a specific solution.

Next step

When current software limits an important process, you do not need to decide immediately between rebuilding it completely or keeping it. The sensible next step is to organise the problem, scope and dependencies so you can assess alternatives effectively.

If you would like to discuss which part of your system should be retained, improved or reconsidered, you can tell AVSISTEC about your application or bespoke software project.