As the end of 2025 rapidly approaches, product businesses everywhere are deep in the holiday shopping rush.
Your focus is on delighting customers and closing out Q4 as a profitable success. Yet behind the scenes, a familiar stress lingers, counting pallets in the warehouse, reconciling numbers in QuickBooks Online, and wondering whether all that manual work is actually working against you.
That concern is well-founded.
Manual inventory processes don’t just slow you down; they actively introduce risk. Without modern inventory technology, errors are unavoidable and worse, many of them go unnoticed until they show up as lost revenue, frustrated customers, or strained cash flow.
This guide explores the most common inventory management mistakes product businesses make and explains how modern solutions like Cin7 help eliminate those mistakes before they impact your bottom line.
Original content notice: This article was originally written and published by Cin7, a global leader in connected inventory management software. The content has been adapted and republished here with attribution.
Outdated Practices and the Common Mistakes to Leave Behind which could cost your business
Inventory errors rarely exist in isolation. They compound over time.
A single data entry error, typing “200” instead of “20” can lead to overstocking, excess storage costs, inaccurate purchasing decisions, fulfilment issues, and damaged customer trust. What starts as a minor mistake can escalate into thousands of dollars in losses and operational disruption.
Understanding these mistakes is the first step toward eliminating them. Below are the nine most common inventory management mistakes, presented exactly as in the original Cin7 article, along with the risks they create.
Mistake #1: Manual Spreadsheet Management
If you’re one of the 26% of businesses Gartner says is using spreadsheets to manage their daily inventory operations (and/or part of the 41% using other manual methods), then you’re struggling with some major challenges, like the data entry issues we just addressed.
In addition to being error prone, spreadsheets can’t give you real-time visibility into your inventory and trying to control the different versions of your spreadsheet is a nightmare. Also a nightmare? Your inability to scale because simple spreadsheets are not designed to handle multi-channel complexity.
Mistake #2: Reactive Reordering
Ever experienced a stockout? Not only were you unable to provide your customers with a desired product, but you also had to do an emergency order…at a premium price. The additional cost for reactive reordering, the potentially lost sales (not all customers will wait!), and the trust issues stemming from your lack of inventory all kill momentum and leave you scratching your head as to how it happened in the first place.
Mistake #3: Ignoring Dead Stock/Overstock
The answer to running out of stock is to ensure you have more than you need, right? Sort of. Keeping safety stock (enough to meet anticipated surges in demand) on hand is good but chronically overflowing your shelves is a recipe for disaster.
With too much inventory, you’re:
- Tying up cash with slow-moving inventory
- Marking down prices
- Paying storage costs
Encouraging overstocking or ignoring dead stock that comes from poor forecasting (e.g., using your gut or not identifying trends early) drains your profit and your energy, it’s a lose-lose situation.
Mistake #4: Single-Channel Thinking
For today’s product businesses, single-channel thinking is a no-go. While operating with only one sales channel may have worked in years past, customers now demand multiple sales channels for flexible shopping options.
With multi-channel operations, you can expect more sales and happier customers. Keep in mind that these benefits are only possible when your inventory is synchronised across all your sales channels and you’re catching any overselling and order cancellations before they happen through diligent inventory monitoring.
But what if you can’t shake the single-channel mindset? Then the benefits are just a dream.
Mistake #5: Flying Blind on Metrics (or Using it Too Late)
Tracking metrics may sound like an enterprise-level thing to do, but it’s an essential task for any size business. Metrics provide the information you need to make proactive, not reactive, decisions (remember our reactive reordering mistake?).
Let’s say, for instance, you’re not tracking your inventory turnover. What happens? You have no clue what stock is moving and what stock is standing still, and because you don’t know, you may be tying up cash in holding costs and creating an unoptimised inventory environment.
Let’s say, however, that you decide to review your metrics reports after problems occur. Too little, too late. You’re missing demand patterns and seasonal shifts, and this missing leads to ordering incorrectly, crushing your profit margins in the process.
Mistake #6: Poor Supplier Communication
As a product business, your suppliers play a key role in your success, but unless they’re psychics, they can’t read your mind. What does this mean? It means that without clear communication from you, they won’t know what supplies you need, nor when you need them.
Additionally, if you provide inconsistent lead times, you’ll get inconsistent deliveries as well as supply chain disruptions due to a lack of coordination on your part. It’s a sure fire way to damage vendor relationships and torpedo customer satisfaction.
Mistake #7: No Returns Strategy
If there’s one thing you can count on as a product business, it’s returns. A study by the National Retail Federation (NRF) and Happy Returns (a UPS company) projected that $890 billion of goods sold in 2024 would be returned, which adds up to 16.9% of annual sales.
Now imagine that you don’t have a returns strategy in place to manage the portion of returns coming your way, or if you do, it’s an inefficient process. You don’t have to use your imagination to know that your customers will not be thrilled. You won’t be either when you find out that your returned items are in inventory limbo and that you’ve lost opportunities to resell or refurbish your products so that you can recoup some of your losses.
Mistake #8: Disjointed Systems and Poor Visibility
Working with disjointed systems will put a major glitch in your inventory management game. When sales, purchasing, and accounting tools don’t talk to each other, errors multiply, just like they do with spreadsheets. In addition to poor inventory visibility, you’ll experience a disconnect between stock levels and cash flow, your COGS calculations will be inaccurate, and you’ll make poor purchasing decisions.
Mistake #9: Failing to Plan for Seasonality and Growth
Finally, not taking seasonal spikes and your growth (due to new channels and markets) into consideration when managing your inventory can result in inventory chaos. Underestimating how much you need? Stockouts. Overestimating? Wasted stock.
This final mistake along with the eight prior, is why you need to adjust your thinking as you head into the New Year.
The 2026 Mindset Shift
The inventory management habits that held businesses back in 2025 will only become more costly in 2026.
The shift forward is clear: move from reactive decisions to predictive planning. Replace disconnected tools and spreadsheets with an integrated inventory management platform like Cin7, designed to unify sales channels, automate workflows, and provide real-time visibility across your entire operation.
Cin7 customers like Brain Dead demonstrate what’s possible when inventory management evolves. After outgrowing spreadsheet-based processes, Brain Dead implemented Cin7 and transformed their global operations, eliminating errors, improving planning accuracy, expanding internationally, and empowering teams with reliable data.
As Brain Dead’s logistics manager Amanda shared, “We wouldn’t have been able to expand globally without Cin7.”
Conclusion: Supported by Profit Mojo, a Trusted Cin7 Partner
Cin7 provides the technology, but successful implementation and long-term value often depend on expert guidance.
That’s where Profit Mojo comes in.
As a trusted Cin7 partner, Profit Mojo helps product businesses unlock the full power of Cin7, optimising inventory processes, integrating financial systems, and ensuring data-driven decision-making from day one. With deep expertise in inventory, accounting, and operational strategy, Profit Mojo ensures that businesses don’t just adopt Cin7, but truly benefit from it.
By combining Cin7’s connected inventory management platform with Profit Mojo’s implementation and advisory expertise, businesses can confidently leave these inventory mistakes behind and step into 2026 prepared, profitable, and scalable.
If you’re ready to work smarter, not harder, Cin7 and Profit Mojo are the partners to help you get there.