5 Common PPC Mistakes: Discover How to Avoid Them and Increase Your Efficiency

Production Planning, Scheduling, and Control ( PPC ) is a cornerstone of effective operations management for any manufacturing company . It's an intricate process encompassing a range of vital activities, from demand forecasting to real-time production monitoring. However, meswith the increasing sophistication of available tools and technologies, common PPC errors persist and can significantly harm operational efficiency, customer satisfaction, and financial results. In this article, we will explore some of the most frequently made PPC errors and examine practical strategies for avoiding them.
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The PPC only sees the stock present in each sector that will program. Each sector only sees what it has "in stock" to program.
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When each department's scheduling focuses solely on what's available in its immediate inventory, unless the department has a massive inventory (which in itself is a problem), there will certainly be a lack of synchronization between departments, resulting in reduced utilization of manufacturing resources. This occurs because it's impossible to see all future material availability that the department will have, which could generate insights for scheduling that aggregates similar items or reduces waiting times, as departments are better synchronized from a more holistic and integrated perspective. This means that production can be interrupted or delayed because one department fails to recognize the needs of another department and, therefore, fails to place the necessary orders or schedules. Thus, by scheduling solely based on currently available inventory, leadmes (waiting time) for production of items can be significantly higher than necessary, thus generating even more work-in-process (WIP) inventory. Ultimately, this problem can result in delays in product delivery to customers.  
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Calculate Days On Hand Based on the average historical demand instead of looking at how many days covers in future demand
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Calculating Days On Hand, which refers to the number of days current inventory can cover demand, if calculated based on average historical demand instead of considering future demand, can lead to significant negative implications. By relying solely on average historical demand, one risks maintaining inventory levels that do not meet the company . This is because demand can fluctuate over time due to seasonality, market trends, changes in customer purchasing patterns, and other factors not reflected in historical averages. In this case, we see company calculating their days of coverage based on an average, but without considering their existing order book or a projection of trends or seasonality. If we have all the indications that demand will behave in a certain way, or even more, if we already have a firm order book, there is no reason not to consider this information when calculating inventory coverage to have an accurate view of the scenario. Consider a clothing store that sells winter and summer clothes. The purchasing manager decides to calculate the Days On Hand for winter coats based on the average historical demand of recent years. This average indicates that demand for winter coats is generally lower during the summer. However, that year, an unexpected cold wave hits the region during the summer, and demand for winter coats skyrockets. As a result, the store does not have enough stock to meet the unexpected demand. Failing to account for future demand can lead to scenarios where inventory is insufficient to meet sudden demand spikes, resulting in product shortages and lost sales .

Open intermediate product order with the date of the finished
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In many manufacturing processes, a final product is assembled from several intermediate products, which in turn may be composed of other byproducts. APS or MRP needs to coordinate the production of these different levels, ensuring that the intermediate products are ready by the required date for the assembly of the final product. That is, it is necessary to establish partial deliveries for some semi-finished goods, and we still see company without this distinction, which means that all semi-finished and finished goods have their production demanded for the mesperiod. The main objective is to ensure that the final product is completed on the date required by the customer. This requires the synchronization of all production stages, from component manufacturing to final assembly, to avoid delivery delays.

Look capacity in kg, meters or unit and not hours
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When capacity is measured solely in physical units, such as kilograms or meters, the product mix a factory needs to produce is not taken into account. Some products may be more complex, time-consuming, and require more resources than others. Ignoring this variability can lead to problems in resource allocation and meeting delivery deadlines. Furthermore, production management should aim to optimize process efficiency, and this often involves the effective use of time. Ignoring the temporal dimension can lead to situations where a machine or labor remains idle for long periods due to inadequate task allocation. A more comprehensive approach that considers both physical capacity and the temporal dimension is often necessary for effective production management, balancing efficiency, costs, and delivery times. This is often achieved through company resource planning (ERP) systems and appropriate production scheduling strategies.
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Charging production per volume produced, operator chooses what is easier to do instead of the most important 
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Charging production based exclusively on the volume produced, without considering other criteria of quality or importance, can lead to a set of problems known as "dilution effect" or "dilution of metrics". This happens when operators are encouraged to choose easier tasks to accomplish to the most important, because it allows them to achieve production goals with less effort. Thus, operators can neglect the quality of work, as their main objective is to increase production. This can result in low quality products or services that do not meet established standards. The five mistakes discussed reveal common traps that organizations may face, from lack of synchronization between sectors to inadequate capacity measurement and exclusive emphasis on the volume produced. Avoiding these errors and adopting more comprehensive and oriented strategies is essential to maintaining efficient production that meets market demands and achieving operational excellence. Did you like the content? Then you will also be interested in our ebook about 6 key elements in production planning .
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