By Thaddée Leblond · Published · Updated: June 2026
Most ERP projects that derail fail before the software is even chosen — at the framing stage. The most costly mistakes: choosing the tool before the needs, reasoning on price rather than total cost, neglecting teams, underestimating data migration, forgetting change management. All are avoidable.
Mistake 1 — Choosing the tool before the need
This is the mother of all the others. Without process mapping or a requirements specification, you compare sales pitches. What dazzles in a demo is not necessarily what will serve your reality.
Mistake 2 — Reasoning on price, not total cost
The licence price is only the visible part. Integration, data migration, custom development, training and maintenance often weigh more. A budget built on the licence alone is a budget that will explode.
Mistake 3 — Leaving teams out of the project
An ERP touches everyone's daily work. Imposed without consultation, it will be worked around or resented. Involving key users from the framing stage improves the choice and prepares adoption.
Is your organisation ready? The readiness assessment shows where the project is likely to stall — sponsorship, key users, workload, decision capacity — before the tool is chosen. Assess your readiness
Mistake 4 — Underestimating data migration
Migrating all your data "as is" means importing your problems into the new system. Migration is a project in its own right: clean, structure and validate the existing data before switching over.
Mistake 5 — Forgetting change management
A tool nobody embraces stays a dead letter. Training, support, communication, process adjustment: these human dimensions often decide success more than the technology.
Mistake 6 — Wanting everything at once
Trying to cover every need at launch lengthens timelines and multiplies risk. Better a controlled scope, put into production, then enriched in stages.
The common thread
All these mistakes share one root: treating the ERP as a software purchase rather than a transformation project. Upstream framing — processes, needs, full budget, teams — is what separates the projects that succeed from those that get stuck.
Frequently asked questions
Choosing the tool before framing your needs. Without process mapping or a requirements specification, you buy a demo rather than a suitable solution — and the gaps prove very expensive later.
Because they reason on the licence price, not the total cost: integration, data migration, custom development, training, change management and maintenance. These items often make up most of the bill.
Absolutely. An ERP imposed without users ends up poorly adopted. Involving them in framing and change management is as much a condition of success as the technical choice.
Not without sorting. Data migration is a project in itself: cleaning, structuring and validating the existing data before migrating. Trying to carry everything over imports the past's problems into the new system.
Sources
- Lessons learned from SME ERP projects (framing, total cost, change management)