Operational Visibility: Why WMS & ERP Data Don't Match

Executive Summary

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Why your WMS and ERP reports don't match

It’s a familiar scene. In the Monday morning meeting, the Head of Warehouse Operations reports that 98% of orders were dispatched on time last week, a figure taken directly from the WMS. A moment later, the Head of Finance raises a concern about a rise in unfulfilled orders, using data from the ERP. The meeting stalls. Both are looking at good data from expensive systems, but the numbers don't add up. The question is, which number is correct?

This sort of thing happens all the time in growing businesses with physical products. You may have moved to the cloud and hired good engineers, but if the underlying process is confused, you've just made the old problems happen more quickly. Trust in the reporting starts to fade, and every decision is based on information you can't quite rely on.

The cause: different systems have different definitions

This isn't an issue with your people, it's a problem with how the systems are set up. The WMS and ERP themselves are probably working perfectly well. The difficulty is that the business logic is split between them. Your WMS might define 'dispatched' as 'the parcel has left the loading bay'. Your ERP might define it as 'the invoice has been generated'. Neither definition is wrong, but they describe different moments in time. Without a way to connect them, it's hard to get a single, clear picture.

In my experience, this is a common problem for growing companies with a physical supply chain. The systems that served you well in the beginning start to cause problems as you scale. The root of it is usually how metric definition is handled. There isn't one central place where business rules are defined and stored. Instead, that logic is often scattered across spreadsheets, in the minds of a few key people, or buried in various SQL scripts. This creates a kind of technical debt, and the cost shows up as day-to-day operational friction.

A practical way to fix this

The temptation is to try and fix the reports, but the problem usually lies deeper. A better approach is to establish a Single Source of Truth that sits above your WMS and ERP and provides a single, consistent view.

This isn't about replacing your main systems. It's about adding a translation layer in your data warehouse. The way I've seen this work well is:

Centralise the logic: First, we take the business logic out of the separate systems and reports. This means getting everyone to agree on one, clear definition for terms like 'Dispatched', 'Stock on Hand', or 'Landed Cost'.

Codify the rules: Next, this shared logic is written into a Semantic Layer in your data warehouse. This makes it a stable, managed part of your data setup, not just a quick fix in a report.

Build from a single source: Finally, all your operational dashboards and reports are built using this unified layer. It doesn't matter if you use Looker, Power BI, or Tableau; the tool gets consistent, reliable data. This means the arguments about whose numbers are right tend to disappear.

This is a core part of a sensible COO Data Strategy. It helps your data team move from constantly fixing reports to building a reliable foundation for the whole business.

This is a business change, not just a technical one

To be clear, putting a single source of truth in place can be challenging at first. You're asking the operations team to change a metric they may have used for years. You're asking the finance team to rely on numbers that don't come directly from their ERP. It's natural for people to be hesitant.

The process is really about getting different departments, which may have worked separately for a long time, to agree on a shared view. It usually needs someone senior to make the final call and say, "This is the number we're all going to use from now on". It might feel like you're slowing down for a few weeks to get this right, but the aim is to move much more quickly and confidently for years to come. It's a trade-off, but one that usually pays off.

What this looks like when it's working

Once this is in place, that Monday morning meeting changes. It stops being a debate about which set of numbers is correct and becomes a discussion about what to do next. You have one reliable view of your operations, from stock in the warehouse to cash in the bank. You can make decisions about where to put your money, feeling confident that the data reflects what's really happening. You spend less time arguing about the numbers and more time thinking about what they mean for the business.