TL;DR:
The decisions that determine whether a SharePoint migration succeeds are not made during migration.They’re made weeks beforehand.This blog covers the decisions that matter most and why getting them wrong is expensive.
Most SharePoint migrations fail because the wrong decisions were made before anyone opened a migration tool.
According to Gartner, 83% of data migration projects either fail or overrun their budgets and schedules. And in 25 years of SharePoint migrations, industry practitioners consistently report the same finding: the difference between a smooth migration and a disaster comes down to preparation.
The decisions that shape a SharePoint migration happen in the weeks before content moves. What gets migrated and what gets archived. Whether the existing folder structure gets copied or redesigned. How permissions are handled — cleaned up or carried forward as-is.
Skipping them moves the cost to a phase where fixing things is three times more expensive and twice as disruptive.
This article explores the key decisions every company should make before starting a SharePoint migration and why investing time in planning is one of the best ways to reduce risk later.
Decision 1: What Really Gets Migrated?
The goal isn’t to migrate everything, but to migrate the right things.
Many companies default to moving every file, every folder, and every version that’s accumulated over the years. It feels like the safest option because nothing gets left behind.
Industry research suggests that up to 30% of enterprise content is duplicate, outdated, or no longer provides business value. Migrating it anyway increases storage costs and creates unnecessary work for users after go-live.
Before migration begins, content should be reviewed and classified into four categories:
- Migrate – Active content that continues to support daily business operations.
- Archive – Older content that must be retained for legal purposes.
- Delete – Content with no ongoing business or regulatory value.
- Deduplicate – Multiple copies or outdated versions where only the latest version is needed.
Tzunami’s Pre-Migration Analyzer helps companies make these decisions with confidence by analyzing the source environment before migration begins. It provides visibility into data volume, file distribution, invalid file names, unsupported path lengths, and other issues that should be addressed before content is migrated.
Decision 2: Copy the Structure or Improve It?
One of the biggest temptations during a SharePoint migration is to recreate the existing environment exactly as it is.
After all, users already know where everything lives.
The problem is that many existing environments have evolved over years of growth, acquisitions, department changes, and one-off business requests. Deep folder hierarchies, inconsistent naming conventions, duplicated libraries, and outdated site structures often become the new normal.
Migrating that structure without questioning it simply transfers yesterday’s problems into tomorrow’s SharePoint.
Instead of asking:
“How do we copy our current structure?”
Ask:
“How should our information be organized for the next five years?”
That question changes the entire migration strategy.
For example, a department might currently store documents across dozens of folders because that’s how the legacy system evolved over time. In SharePoint, those same documents could be organized using metadata, making them easier to search, filter, secure, and manage without relying on complex folder structures.
Making these decisions before migration begins is far easier than trying to reorganize live content after users have already adopted the new environment.
Decision 3: What Happens to Permissions?
Permissions are one of the most important parts of any SharePoint migration plan and one of the most commonly overlooked.
The easiest approach is to copy every permission from the source system into SharePoint. That works if your permissions are already clean and well-managed. For many companies, however, it means carrying years of permission sprawl into a new environment.
Think about everything that changes over time:
- Employees leave the company.
- People move to different departments.
- Temporary project teams are created.
- External users are granted access that is never removed.
If these permissions are migrated without review, the new SharePoint environment inherits the same security issues as the old one.
A SharePoint migration is the perfect opportunity to clean things up.
Before migration begins, companies should decide:
- Which permissions should remain?
- Which users or groups no longer need access?
- Should broken inheritance be simplified?
- Can direct user permissions be replaced with group-based access?
Permissions should reflect today’s business, not yesterday’s.
Tzunami Deployer migrates users, groups, and permissions alongside content while supporting permission mapping between source and SharePoint environments. For companies migrating from systems like Documentum, OpenText, or Confluence, it helps preserve the correct security model while supporting cross-domain migration scenarios.
Decision 4: How Will Metadata Move?
Files are only part of what makes SharePoint valuable.
Metadata is what makes information searchable, filterable, compliant, and useful long after the migration is complete.
It powers search, workflows, retention policies, and increasingly helps Microsoft 365 Copilot deliver more accurate, context-aware responses. Yet it’s one of the areas companies spend the least time planning.
Without a metadata strategy, content often arrives in SharePoint as little more than a collection of files. Before migration starts, companies should answer a few key questions:
- How will source fields map to SharePoint columns?
- Which managed metadata terms need to exist before migration?
- How will invalid values be corrected?
- What happens to fields that don’t have a SharePoint equivalent?
These decisions are much easier to make before content moves.
If the required metadata structure isn’t ready, documents may arrive with empty managed metadata fields or incorrectly mapped values. Fixing those problems afterward often requires additional migration work that could have been avoided through proper planning.
Tzunami Deployer automatically maps metadata from the source repository to SharePoint while helping correct invalid values during the migration process.
Decision 5: Define Success Before the Migration Starts
Many migration projects define success with a single number:
100% migrated.
Unfortunately, that number doesn’t tell the whole story.
A migration can complete successfully while users still experience missing permissions, broken links, incomplete metadata, or documents that can’t be found through search.
Success should be defined before migration begins.
A successful SharePoint migration should validate:
- Content integrity – Item counts, file sizes, and version history match the source.
- Metadata accuracy – Fields are correctly mapped and searchable.
- Permissions – Users can access the content they should—and nothing more.
- Links – Navigation, bookmarks, and embedded links continue to work.
- User acceptance – Employees can complete their daily work without disruption.
Good Planning Creates Better Migrations
Every decision made before migration influences what happens after go-live.
Waiting until content has already moved to redesign permissions, reorganize information architecture, rebuild metadata, or remove outdated content is possible, but it’s significantly more disruptive than making those decisions early.
Summing Up
A successful SharePoint migration starts long before content begins moving.
The decisions you make about what to migrate, how to organize it, how permissions and metadata should work, and how success will be measured have a much greater impact on the outcome than the migration itself.
Taking the time to make those decisions early helps reduce risk, avoid costly rework, and create a SharePoint environment that supports your business from day one.
Frequently Asked Questions
1. What is the most important decision before a SharePoint migration?
Deciding what should be migrated and what should be archived, deleted, or cleaned up. Migrating everything by default often carries unnecessary content into the new environment.
2. Should you copy your existing SharePoint structure?
Not necessarily. A migration is an opportunity to improve your information architecture instead of recreating old problems.
3. When should permissions be reviewed?
Before migration begins. Cleaning up permissions early helps avoid security issues and reduces post-migration work.
4. Why is metadata planning important?
Metadata supports search, workflows, and compliance. Without proper planning, documents may lose valuable business context after migration.
5. How do you know if a SharePoint migration was successful?
Success isn’t measured by file count alone. A successful migration preserves content, permissions, metadata, and links, and allows users to continue working without disruption.
