Bevica Blog

Shadow systems: the hidden cost of side spreadsheets

Written by alexwilliams | May 14, 2026 10:34:20 AM

When you hear the term ‘shadow systems’, you might think of unauthorised third‑party software that your IT Manager would definitely disapprove of. In reality, they’re far more likely to be spreadsheets, shared drives, or side databases that staff build to fill gaps they see in the core ERP. They emerge with good intent, sit outside IT governance, depend on a few individuals, and quietly become critical for pricing, forecasting, or stock checks without ever being formally approved.

In the drinks industry, we most often see shadow systems forming around pricing models, duty and bond tracking, promotions and stock visibility — areas where generic ERP configurations struggle to reflect operational reality.
It’s something we regularly uncover when working with Bevica customers during implementations and ERP reviews.

How your ERP stops being the single source of truth

In growing drinks businesses, these tools often start as harmless stopgaps: a sales pricing workbook for a specific national account, a sheet tracking duty‑paid vs bond, or a quick database for samples. Over time, people begin to trust these more than the ERP.

Because spreadsheets are fast to change, teams add more logic, macros and lookups until the “temporary” workbook effectively becomes a parallel system — one that increasingly drives commercial decisions.

Shadow systems are especially common when older ERPs feel hard to adapt. If a new price structure or discount rule takes weeks to configure centrally, users default to Excel instead. We see this most clearly at month‑end: finance exports trial balances cleanly from the ERP, then rebuilds management views in spreadsheets that slowly evolve into operational models.

How shadow systems quietly damage margin and control

Shadow systems introduce three compounding risks: inconsistent data, opaque decision‑making, and operational fragility.

Because they sit outside the ERP, product, customer and pricing data quickly diverge. A sales team working from an off‑system price file can erode margin long before the impact appears in the P&L and that's if it’s spotted at all.

 

Visibility also suffers. When allocation logic, discount rules or stock calculations live in personal files, answering seemingly straightforward questions becomes difficult:

  • Which customers are on exception pricing this quarter?
  • Which promotions sit outside standard margin models?

The answers exist — but only inside a handful of spreadsheets.

Finally, shadow systems are brittle. When a key individual leaves, critical reporting can fail overnight. In our experience supporting Business Central and Bevica environments, this dependency often adds days to month‑end close as teams reconcile competing versions of the truth.

 

Spotting shadow systems in your drinks business

The first step is surfacing where shadow systems already exist. Look for recurring tasks where someone says, “I’ll just pull it from my spreadsheet.”

Typical hotspots include:

  • Duty and tax calculations
  • Pricing by channel or customer group
  • Promotion and rebate tracking
  • Depletion, sell‑out or stock analysis

You need to ask three simple questions:

  • Which reports would stop if a specific colleague were unavailable?
  • Where is data manually rekeyed between systems?
  • Which files are emailed around every month “just to tidy the numbers”?

Each “yes” usually points to a hidden system that has quietly become operationally important.

 

Replacing shadow systems with Bevica without losing flexibility

The goal is not to ban spreadsheets, but to move critical logic back into a governed ERP platform such as Bevica, powered by Microsoft Dynamics 365 Business Central.

In TVT implementations, we start by prioritising shadow systems that affect pricing, margin, compliance or stock valuation. These are the areas where errors are most costly. We then translate what spreadsheets are doing into structured configuration: customer‑specific pricing, approval workflows, campaign dimensions and duty logic that work for drinks businesses.

Just as important is change management. Teams stop relying on shadow systems when the ERP gives them faster, clearer answers. That means dashboards and reporting that genuinely replace personal workbooks, and agreement that Bevica is the system of record.

Over time, reconciliation effort falls, confidence in the numbers improves, and the quiet margin leakage caused by unmanaged side systems disappears.

Shadow systems aren’t usually a discipline problem. They’re a system design problem and with the right ERP and implementation partner, they don’t need to exist.