Welcome to Stock Control!
In this chapter, we are looking at Resource Management. Think of stock control as the "Goldilocks" of business: you don't want too much stock, and you don't want too little—you want it to be just right. Whether it's a supermarket keeping milk on the shelves or a car factory waiting for engines, managing stock is vital for keeping customers happy and costs low.
Don't worry if this seems tricky at first! We’re going to break it down step-by-step using simple ideas you already know from everyday life.
1. The Stock Control Diagram (The "Sawtooth" Chart)
In your exam, you might see a graph that looks like the teeth of a saw. This is the stock control diagram. It shows how stock levels drop as they are used and then jump back up when a new delivery arrives.
Let's break down the key parts:
1. Maximum Stock Level: The most stock a business can (or wants to) hold. This is limited by the size of the warehouse or the money available to buy it.
2. Minimum Stock Level (Buffer Stock): This is the "emergency" level. A business aims to never go below this line. Think of it like the "low battery" warning on your phone—you still have power, but you need to act fast!
3. Re-order Level: This is the "trigger point." When stock falls to this specific number, the business places a new order with its supplier.
4. Lead Time: This is the time gap between placing an order and the stock actually arriving at the warehouse.
5. Re-order Quantity: The amount of stock actually ordered from the supplier.
Analogy: Imagine your kitchen cupboard. Your "Maximum Level" is 10 boxes of cereal. Your "Re-order Level" might be 3 boxes. If it takes 2 days for your online shopping to arrive, that 2-day wait is your "Lead Time."
Key Takeaway: The diagram helps a business visualize when to order so they never run out (stock-out) but also don't overfill the warehouse.
2. Buffer Stocks: The Safety Net
Buffer stock is the extra stock held "just in case" something goes wrong. Why would a business pay to keep extra stock sitting around?
• Sudden demand: A heatwave might lead to a sudden rush for ice cream.
• Supplier delays: A delivery truck might get stuck in traffic or break down.
• Faulty batches: Some items might arrive damaged and cannot be used.
Quick Review: Buffer stock is like a spare tyre in a car. You hope you don't need it, but you're glad it's there if you get a puncture!
3. The Implications of Poor Stock Control
Managing stock badly usually means having too much or too little. Both are expensive mistakes.
Problem A: Having TOO MUCH stock (Overstocking)
• Storage Costs: You have to pay for bigger warehouses, heating, lighting, and security.
• Wastage: Items might go past their "use-by" date or become obsolete (outdated), like old fashion trends or older phone models.
• Opportunity Cost: Your money is "tied up" in boxes on a shelf. You could have used that money for advertising or new equipment instead.
Problem B: Having TOO LITTLE stock (Stock-outs)
• Lost Sales: If a customer sees an empty shelf, they will go to a competitor.
• Halted Production: If a factory runs out of one tiny screw, the whole assembly line might have to stop.
• Damaged Reputation: Customers lose trust in a business that is always "out of stock."
Memory Aid: Think of S.O.W. for the costs of holding stock: Storage, Opportunity cost, and Wastage!
4. Just in Time (JIT) Management
Just in Time (JIT) is a modern way of managing stock. Instead of keeping a big "buffer" in a warehouse, the business orders stock so that it arrives exactly when it is needed for production or sale.
How it works:
It is a "Pull" system. Stock is only ordered when there is an actual customer order. This means the warehouse stays almost empty.
Advantages of JIT:
• No money is tied up in stock (better cash flow).
• No waste from old or damaged stock.
• No need for huge, expensive warehouses.
Disadvantages of JIT (The Risks):
• No room for error: If a supplier is 10 minutes late, production stops.
• No bulk buy discounts: Ordering small amounts frequently can be more expensive than one big order.
• High transport costs: Lots of small deliveries mean more delivery fees and more CO2 emissions.
Did you know? JIT was famously perfected by Toyota in Japan. They realized that "waste" is anything that doesn't add value to the customer—and sitting in a box on a shelf doesn't add value!
5. Waste Minimisation and Lean Production
Stock control is a huge part of Lean Production. "Lean" simply means cuting out the "fat" (waste) from a business to become more efficient.
Waste Minimisation involves looking at every part of the stock process to stop resources from being thrown away. This could mean:
• Improving quality so items aren't broken.
• Using JIT to ensure items don't go out of date.
• Better training so staff don't make mistakes with stock.
Competitive Advantage:
By being "Lean" and managing stock perfectly, a business can lower its costs. This gives them a competitive advantage because they can either sell their products for a lower price than rivals or keep more profit for themselves.
Key Takeaway: Lean production isn't just about stock; it’s a mindset of "doing more with less."
Final Quick Review
Common Mistake to Avoid: Don't confuse Lead Time with Stock Rotation. Lead time is how long you wait for your order to arrive from a supplier.
Checklist for your Revision:
• Can I label the Maximum, Minimum, and Re-order levels on a graph?
• Do I understand that "Lead Time" is a horizontal measurement of time?
• Can I explain why a business would choose to hold Buffer Stock (the "Just in Case" method)?
• Can I list two pros and two cons of Just in Time (JIT)?
• Do I see how Waste Minimisation leads to higher profits?
You've got this! Stock control is all about balance. Master the diagram, and you've mastered the chapter!