Data migration is one of the riskiest IT projects you’ll ever run. Done well, it enables transformation, efficiency, and growth. Done badly, it can lead to lost data, blown budgets, security gaps, and frustrated users. In fact, studies show that a significant percentage of migrations run over time, over budget, or outright fail – often because of avoidable mistakes.
In this post, we’ll cover the five most common data migration mistakes that organisations make (and how to avoid them). Whether you’re moving to the cloud, consolidating legacy systems, or upgrading your infrastructure, avoiding these pitfalls could save your entire project – and your reputation.
1. No Clear Strategy
Jumping into a migration without a mapped-out plan is like trying to rebuild a plane mid-flight. You might make it, but the risks are sky-high.
A solid migration strategy isn’t just a high-level idea, it’s a detailed roadmap. It should cover:
- Timelines and milestones – when each stage will happen
- Dependencies – what must happen before something else can proceed
- Downtime windows – when disruption will occur (and how to minimise it)
- Rollback plans – how to recover quickly if something goes wrong
A clear strategy ensures everyone knows what success looks like and how to get there. Without one, you’re essentially gambling with your organisation’s data.
2. Underestimating Data Complexity
On paper, data looks simple: numbers in a table, fields in a database, documents in a folder. In reality, it’s rarely that clean.
Data is:
- Connected – records often link across multiple systems
- Layered – built up over years (or decades) of business processes
- Messy – duplicates, inconsistencies, and legacy formats are common
One of the biggest issues we see at Dajon is teams realising too late just how entangled their legacy data is across platforms. By then, the migration is already underway, and the project starts slipping.
The fix: carry out a thorough data assessment before you start. Map your data sources, dependencies, and quality issues early – so there are no nasty surprises later.
3. Skipping Testing
Would you deploy a new app without testing it? Probably not. So why do so many organisations skip proper testing during a migration?
Testing should happen at every stage of the process:
- Before migration – validate that your data sets are complete and consistent
- During migration – run pilots, partial transfers, and integrity checks
- After migration – confirm that everything landed correctly and works as expected
End-to-end testing isn’t optional; it’s your safety net. Skipping it is like jumping out of a plane and hoping the parachute opens by itself.
4. Forgetting End Users
This is the most overlooked aspect of migration projects. A flawless technical migration does not guarantee success.
If your end users can’t access, navigate, or understand the new system on day one, your migration has failed in their eyes. And remember, if the people who rely on the data every day aren’t happy, the project hasn’t truly succeeded.
That’s why communication and training must be part of your migration plan. Tell users what’s changing, when, and why. Provide training sessions, guides, and support channels. And don’t underestimate the value of early feedback from a pilot user group.
5. Overlooking Security
Finally, never assume the destination environment will “take care of” security. Migration introduces risks that must be proactively managed.
Consider:
- Secure transmission – is your data protected while it’s in motion?
- Encryption – are sensitive files encrypted both in transit and at rest?
- Access controls – are permissions and authentication correctly configured post-migration?
Failing to address security properly doesn’t just open the door to breaches; it also exposes you to audit failure, regulatory penalties, and reputational damage.
Final Thoughts
Data migration is one of the most critical – and riskiest – IT projects an organisation can undertake. The five mistakes above are the ones we see most often, but they’re also the ones most easily avoided with the right planning, testing, and oversight.
At Dajon Data Management, we’ve helped countless teams navigate complex migrations successfully. Whether you need a detailed roadmap, a second opinion on your strategy, or hands-on support, we’re here to help.
If you’re planning a migration, don’t leave it to chance. Reach out today and let’s make sure your project lands smoothly.