In manufacturing, many forms of inefficiency can be hard to detect until they significantly impact productivity, profitability, and performance. These are known as the six big losses, and they represent the most common causes of wasted time and resources on the factory floor.

Fortunately, Overall Equipment Effectiveness (OEE) is designed to identify, measure, and reduce these losses. With real-time visibility into machine and process data, OEE enables businesses to detect hidden inefficiencies, streamline operations, and increase output without additional investment in equipment.

What are the "Six big losses"?

The six big losses fall under three OEE components: availability, performance, and quality. Each type of loss targets a specific source of inefficiency that reduces your plant's overall productivity.

Let’s explore each one and how OEE helps to resolve it.

1. Equipment breakdowns (Unplanned Stops)

Breakdowns are one of the most visible and costly forms of availability loss. When machines fail unexpectedly, production halts, leading to wasted time, missed deadlines, and potential revenue loss.

How OEE helps:
A OEE system provides real-time production monitoring, allowing you to track machine health continuously. By identifying failure patterns and performance anomalies early, maintenance teams can take proactive action before breakdowns occur. This not only reduces downtime but also extends the lifespan of critical assets.

2. Setup and adjustment time (Planned Stops)

Every time a machine requires changeovers, tooling adjustments, or calibration, it results in planned downtime. Although necessary, excessive setup time reduces availability and delays production schedules.

How OEE helps:
With downtime tracking and categorisation, OEE software like MaintMaster OEE highlights which machines and processes suffer from frequent or prolonged adjustments. This insight helps teams reduce setup times through standardised procedures, better operator training, and smarter scheduling.

3. Minor stops (Micro stoppages)

Minor stops refer to frequent, short interruptions—typically less than five minutes—that cause machines to pause unexpectedly. These include jams, sensor blockages, or brief pauses in material flow.

How OEE helps:
OEE software logs and alerts teams to micro stops in real time. When linked to automated machine data, these events are no longer invisible. Technicians are notified immediately, allowing for quick resolutions. Over time, recurring root causes can be addressed to prevent future stoppages entirely.

4. Reduced speed (Slow cycles)

When machines run slower than their ideal cycle time, the result is lost productivity. This performance loss is often overlooked, yet it can account for substantial hidden waste across a shift or production cycle.

How OEE helps:
By benchmarking actual performance against ideal cycle times, OEE softwares makes slow-running equipment visible. Alerts can be triggered when speed drops below defined thresholds, enabling swift corrective action. Additionally, aggregated data can reveal trends and bottlenecks, helping to optimise line performance.

5. Reduced yield (Start-up rejects)

Start-up losses typically occur during warm-up or ramp-up phases. These are the defective units produced between machine start-up and stabilisation, often resulting from suboptimal conditions or insufficient preparation.

How OEE helps:
With yield monitoring and quality tracking, OEE systems can detect patterns in start-up rejects, such as recurring problems at certain times, shifts, or machines. This information helps refine your start-up procedures and reduces waste generated during non-steady-state production.

6. Process defects (Production rejects)

This final category refers to defective units produced during steady-state production. These issues increase rework and scrap rates, affect customer satisfaction, and inflate operational costs.

How OEE helps:
Modern OEE software integrates with machine-level controls to track quality in real time. This ensures teams can quickly identify where and when defects occur. By pinpointing the root cause—whether it’s a faulty component, worn tooling, or operator error—corrective action can be taken to improve quality and minimise losses.

Why tackling the six nig losses matters

Eliminating the six big losses isn’t just about increasing your OEE score—it’s about building a more efficient, reliable, and profitable operation.

Benefits include:

• Reduced downtime and repair costs

• Higher throughput with existing assets

• Greater customer satisfaction through consistent quality

• Stronger team accountability and engagement

• Improved ROI from continuous improvement efforts

The key is visibility. Without real-time, accurate data, these losses often go undetected. But with the right tools in place, such as MaintMaster OEE, manufacturers can gain full insight into what’s happening on the shop floor—minute by minute.

Six Big Losses and OEE: A strategic match

The six big losses framework is perfectly aligned with the availability, performance, and quality components of OEE. Here’s how they map:

Use MaintMaster OEE as your loss-elimination tool

The six big losses may seem like small issues when viewed in isolation—but together, they can erode hours of productivity and cost thousands in wasted materials, labour, and energy. That’s why understanding, tracking, and eliminating these losses is essential.

OEE isn’t just a performance metric, it’s a strategic framework for continuous improvement. With MaintMaster OEE, manufacturers gain the visibility and insights needed to eliminate inefficiencies at their source and transform operations from reactive to proactive.