From firefighting planners to stable, predictable supply chains, Episode 17 of the D365 Insights Podcast explores one of the most misunderstood areas of ERP: planning.

We sat down with Roger Fleury, a planning expert with over 30 years of experience across manufacturing, ERP implementations, and Dynamics AX/D365, to understand why planning so often goes wrong and what organisations can do differently.

What stood out was not only Roger’s technical knowledge, but also his perspective that planning challenges are rooted in people, processes, and mindset as much as in the system itself.

Here are some of the key takeaways from the conversation:

1. Planning success depends as much on organisational alignment as it does on system logic

One of the biggest misconceptions Roger highlighted is that planning can be “solved” with software alone.

In reality, planning sits at the intersection of sales, operations, finance, warehousing, and procurement. If those functions aren’t aligned, no system — including D365 — will produce meaningful outputs.

Planning isn’t about generating numbers; it’s about ensuring the entire business is working toward the same outcome. Without that alignment, even the best-configured system will struggle.

2. Master Planning (MRP) was never built for today’s complexity

Traditional MRP remains at the heart of many D365 environments — but Roger was clear about its limitations.

Originally designed decades ago, MRP assumes a relatively stable world and produces a single “perfect” plan based on fixed inputs. Modern supply chains, however, are anything but stable.

The result?

• Constant changes in recommendations

• Lack of stability

• Heavy reliance on manual intervention

As Roger put it, the same plan can produce entirely different outputs day to day or even within the same day.

3. Reliance on Excel is often a symptom rather than the root cause of the problem

It’s common to see planning teams fall back on Excel, even after investing in D365.

But rather than blaming the tool, Roger reframed the issue:

Excel represents flexibility, visibility, and control, all of which planners often feel they lack in ERP systems.

The risk, however, is significant:

• “Islands” of disconnected data

• Undocumented logic

• Dependency on individuals

The goal shouldn’t be to eliminate Excel entirely, but to understand why it’s being used and address those underlying gaps.

4. The biggest impact often comes from behaviour and decisions rather than the data itself

While poor data often gets blamed for planning issues, Roger emphasised that the biggest disruptions are usually caused by internal decisions and behaviours.

Examples include:

• Finance pushing stock reductions at year-end

• Sales driving demand spikes to hit targets

• Conflicting KPIs across departments

These decisions create volatility that no system can fully absorb. The challenge is not to eliminate variability but to design planning processes that can respond to it effectively.

5. Stability beats perfection every time

A recurring theme throughout the discussion was the importance of stability over precision.

Traditional planning aims for a perfectly balanced supply and demand plan. However, because forecasts are inherently inaccurate, this often leads to constant re-planning and firefighting.

Roger suggests a different approach:

• Accept that forecasts are wrong

• Plan within ranges, not exact figures

• Use buffers to absorb variability

This shift enables planners to move from reactive execution to controlled, predictable flow.

6. Planners are often firefighting instead of adding value

In many organisations, planners and buyers spend most of their time chasing issues:

• Expediting orders

• Responding to shortages

• Managing exceptions

This leaves little time for higher-value activities like supplier management, process improvement, or strategic planning.

A successful planning setup should remove noise from the system, giving teams the bandwidth to focus on what actually matters.

7. The biggest implementation mistake: recreating the past

One of the most common pitfalls in D365 projects may seem simple at first yet it often proves costly.

Organisations replace their system but replicate the same processes.

Under pressure to deliver quickly and minimise risk, teams default to “what we already do.” The result is a new system that looks better, but fails to drive real change.

True transformation requires stepping back and asking:

• Why do we do this?

• What are we actually trying to achieve?

• Is there a better way?

8. People and mindset matter more than configuration

While system setup is important, Roger stressed that planning success is driven by people.

Key challenges often include:

• Lack of planning education

• Limited understanding of system configuration

• No ownership of ongoing optimisation

Unlike other ERP areas, planning configurations need to evolve constantly. Without internal knowledge and ownership, systems quickly become outdated.

9. Good planning is defined by one thing: delivering for the customer

When it comes to measuring success, Roger kept it simple.

The most important KPI is: 👉 On Time In Full (OTIF) delivery to the customer

While many organisations track dozens of metrics, not all drive the right behaviours. In fact, some — like maximising production output — can actively harm the overall flow.

The key is ensuring KPIs support the end-to-end supply chain, not just individual departments.

10. The starting point is education rather than data

For organisations beginning or resetting their planning journey, Roger’s advice was clear:

Don’t start with data clean-up or system configuration. Start with education and mindset change.

Planning teams need to understand:

• What’s possible today

• Why traditional approaches fall short

• How different methodologies (like buffer-based planning) can help

Only then can meaningful change take place.

Final thought

This episode was a reminder that planning is not about creating the perfect plan. It is about building a resilient and adaptable system that works in the real world.

As Roger put it:

If you keep doing the same thing, don’t expect a different result.

For organisations investing in D365 Supply Chain, the opportunity is not only to upgrade their software but also to rethink how planning works altogether.

🎧 You can listen to the full episode on Spotify, YouTube, or wherever you get your podcasts — just search 365 Insights by Source & Connect.