ERP is often sold as the thing that will finally bring everything together. One system, clear data, smoother operations.
In manufacturing, that promise is real. But getting there is rarely straightforward. Most ERP projects that struggle do so for the same reasons. Not because the software is wrong, but because of how the project is approached.
Here are the most common mistakes manufacturers make, and how to avoid them.
1. Starting Without Clear Goals
The mistake is simple. “We need an ERP” becomes the goal.
Without a clear definition of success, projects lose direction. Scope grows, priorities shift, and teams start pulling in different directions.
In manufacturing, this often shows up as trying to fix everything at once. Inventory, production, procurement, reporting. All in one go.
How to avoid it:
- Define a small number of measurable outcomes
- Focus on what matters most first
- Be strict about what gets included in phase one
If you cannot clearly explain what success looks like, the project will struggle to get there.
2. Treating Manufacturing Like Anything Else
ERP is not just a back-office tool in manufacturing. It sits at the heart of operations.
When manufacturing needs are not properly considered, the system might work on paper but fail on the shop floor. This is where BOMs, routings, scheduling, and traceability really matter. Miss these, and people will find workarounds.
Usually, that means spreadsheets come back.
How to avoid it:
- Map real production processes before implementation
- Involve people from the shop floor early
- Choose a system and partner with manufacturing experience
3. Underestimating Time and Effort
ERP is often treated like a software install. In reality, it is a business-wide change. The biggest gap is usually internal. People still have their day jobs, and ERP becomes an extra layer on top.
How to avoid it:
- Plan realistically for time and internal involvement
- Assign dedicated internal owners
- Expect disruption and build around it
The real cost of ERP is not just the system. It is the time your business needs to change.
Case in point: Hershey
Hershey’s ERP rollout is one of the most widely cited examples of what happens when scope and timing are misjudged.The company tried to implement multiple major systems at once and compressed the timeline significantly. They also went live just before a peak sales period.
The result was major order fulfilment issues and an estimated $100 million in lost sales.
Takeaway: too much change, too quickly, without aligning to operational reality.
4. Treating Data as an Afterthought
Data issues do not show up until it is too late.
Duplicate part numbers, messy BOMs, and inconsistent units. These problems get carried into the new system and become more visible, not less.
In manufacturing, poor data directly affects planning, inventory, and production.
How to avoid it:
- Clean and standardise data before migration
- Assign ownership for different data sets
- Test with real scenarios
At the end of the day, ERPs depend on good data.
5. Skipping Training and Change Management
It is easy to focus on the system and forget the people using it.
When teams are not properly trained or involved, they fall back on what they know. Spreadsheets, manual workarounds, and side systems. This is one of the biggest reasons ERP projects fail to deliver value.
How to avoid it:
- Train people based on their actual roles
- Involve users early
- Explain why the change is happening
Go live not when the system is ready, but when the relevant people actually know what to do.
Case in point: Revlon
Revlon’s ERP challenges are a good example of what happens when operational impact and user readiness are underestimated.
Following its implementation of a new ERP system, the company experienced significant disruptions across its supply chain. Orders could not be fulfilled properly, and inventory visibility broke down.
In financial disclosures, Revlon cited these issues as a contributing factor to missed sales and customer service problems. A key part of the challenge was not just the system itself, but how it was adopted and used in day-to-day operations.
Takeaway: even when the system is in place, lack of training and operational readiness can directly impact revenue.
6. Trying to Customize Everything
There is always a temptation to recreate every existing process in the new system. It feels safer. Familiar. Less disruptive.
But it often leads to higher costs, longer timelines, and systems that are harder to maintain.
How to avoid it:
- Challenge existing processes
- Use standard functionality where possible
- Customize only where it adds clear value
If you’re trying to improve how things work, then why replicate the system you’re trying to replace?
7. Weak Ownership and Leadership
ERP projects need clear ownership. When responsibility is unclear, decisions slow down. Priorities clash. Progress stalls.
This is especially common when the project is left entirely to IT or external partners.
How to avoid it:
- Appoint a strong internal project lead
- Ensure executive sponsorship
- Build a cross-functional team
Final Thought
Most ERP challenges are not technical. They are organizational.
The manufacturers who succeed treat ERP as a business change grounded in how their operations actually work.
Get that right, and the system becomes what it was meant to be. A tool that supports the business, not something the business has to work around.