What is the most common ERP mistake?

Starting without a clear written scope and an internal owner. Almost every other problem grows from that.

Should we run old and new systems in parallel?

Briefly, to verify results. Running both for months doubles the work and delays adoption.

When is an ERP project really finished?

When the team uses it for daily work and the reports are trusted, which is usually reviewed 30 to 90 days after go-live.

10 ERP Implementation Mistakes to Avoid

Most failed ERP projects fail for ordinary reasons: unclear scope, weak ownership and untrained users. All of them can be prevented.

The mistakes

Mistake	What to do instead
1. No written scope	List modules, users, branches and integrations before signing
2. No internal owner	Name one project owner with authority
3. Migrating dirty data	Clean masters and reconcile opening balances
4. Customising everything	Change process first; customise only real gaps
5. Skipping training	Role-based training before go-live
6. Big-bang go-live of every module	Phase modules
7. Running old and new in parallel for months	Short, planned parallel run only
8. Ignoring reports	Define the reports you need up front
9. No post go-live support plan	Agree support period and contacts
10. Declaring victory at go-live	Review usage and fix process gaps at 30 and 90 days

A simple safeguard

Hold a short weekly review during the project with the vendor, the project owner and one representative per department. Keep an issue list with owner and date. Most problems are cheap to fix when they are small.