Spare Parts Availability – The Underestimated Competitive Factor in After Sales
“We need the part immediately!”
I heard this sentence countless times during my time as an after-sales manager. And very often, it was not about complex assemblies or special solutions, but about seemingly insignificant spare parts – components whose absence is enough to bring an entire production line to a standstill.
It is precisely these parts that pose major challenges for purchasing, planning, and warehouse organizations in mechanical engineering – and at the same time represent a key lever for customer satisfaction and competitive differentiation.
The Reality of the Spare Parts Business
Both from my years in permanent roles and from numerous projects as an interim manager, a clear picture emerges:
- Around one third of the spare parts ordered by customers within a given year were not sold at all in the previous year.
- Of these items, roughly one quarter had also not been requested in the year before that.
- At the same time, approximately one third of the items sold in the previous year are ordered only in a quantity of one sometimes a low-cost small part, sometimes an expensive gearbox housing.
This high degree of variability makes traditional planning and inventory logic extremely difficult.
Why Conventional Planning Reaches Its Limits
The result is a familiar dilemma:
- Those who stock too much tie up capital and increase the risk of obsolescence.
- Those who plan too tightly risk delivery delays, customer downtime, and long-term loss of trust.
Especially in after sales, availability is not a “nice to have,” but a critical element of the value proposition made to the customer.
Pragmatic Approaches Instead of Crystal-Ball Forecasts
The solution does not lie in ever more complex forecasting models, but in pragmatic, robust strategies that are capable of dealing with uncertainty.
1. Criticality Instead of Sales Frequency
Inventory strategies should not be driven solely by how often a part is sold, but by one key question: Which parts will bring the customer’s production to a halt? These components require clear – and often highly individualized – supply strategies,
regardless of how rarely they are sold.
2. Leveraging Alternative Supply Concepts
These may include, among others:
- Pooling models with partners or subsidiaries
- Repair instead of full replacement
- Stocking semi-finished blanks for high-cost components
- Using 3D printing or alternative manufacturing methods
3. Consistently Managing Minimum and Safety Stock Levels
Systematically defined minimum and safety stock levels must not only be set, but also strictly maintained. Even small lapses can significantly jeopardize availability.
4. Creating Digital Transparency
Digital systems are not only tools for demand forecasting. They must be able to provide immediate answers to questions such as:
- Where is the part currently located?
- What delivery time is realistic?
- What alternatives are available at short notice?
5. Proactive Solution Strategies for Critical Situations
Customers do not necessarily expect every part to be available at all times. What they do expect is that, in an emergency, viable alternatives are offered immediately to keep production running.
Conclusion: Availability Is More Than Inventory Levels
Successful after sales is not determined by whether all parts are permanently in stock.
What truly matters is whether the right parts or solutions are available at the critical moment – or whether the customer is left empty-handed and turns to the competition.
Spare parts availability is therefore not merely an operational issue, but a strategic competitive factor in after sales.
