With an original focus on performance, quality, results, cost, and productivity, Lean is the organization and practice of continuous improvement. In the middle of the 20th century, Lean, the concept of efficient manufacturing/operations, grew out of the Toyota Production System.
The term “Lean” was coined in 1990 following the exploration of the Toyota model that led to the “transference” thesis, sustaining the concept that manufacturing problems and technologies are universal problems faced by management and that these concepts can be emulated in non-Japanese enterprises (Teich and Faddoul 2013). The Lean methodology focuses on performance improvement and team collaboration by eliminating waste.
Why Lean and Reliability Belong Together
Implementing Lean at your facility starts with top-level management and individuals who are focused on the company’s strategic plan. Middle management integrates initiatives across departments, and employees conduct activities daily. Successful implementation of this methodology is a team effort.
Practicing lean methodology in reliability emphasizes risk-based maintenance, predictive analytics, and streamlined processes so personnel can focus only on what adds value, what is reducing downtime, extending asset life, and improving safety. In practicing this, it is important to spot these wastes, understand their root causes, and revise processes to minimize or eliminate them.
Lean isn’t just about cutting waste – it’s about unlocking value, empowering people, and creating reliability that lasts.
Lean manufacturing is a system that improves the process in an organization by using principles and tools to reduce several types of waste (Pérez-Naranjo, M.E., Avilés-Sacoto, S.V., Mosquera-Recalde, G.E., 2021). Lean Manufacturing is not entirely about reducing waste (the lean methodology refers to this as “muda”); it is also about creating value, empowering employees, and improving workflow.
The elimination of the 7 types of waste is one of the many lean manufacturing tools that can be incorporated at your company to transform processes and achieve excellence. In the reliability and maintenance context, waste refers to the concept of wasted resources spent on the poor execution of daily maintenance activities and strategies. This is often project-based, tool-driven, with pressure for quick ROI.
By focusing on waste reduction, continuous improvement, and value maximization, lean methodologies have driven significant advancements in industries such as automotive, aerospace, healthcare, electronics, food and beverage, construction, and retail (Sumi 2024).
In a case study focused on the shutdown maintenance of a feed water pumping station in a stream system at a petrochemical company in Egypt, non-value-added time was reduced by 60%, downtime was decreased by 43% and shutdown efficiency improved from 27% to 49% (Gomaa, 2025).
Implementing lean methodology in a power cable factory increased process performance and production with a 50% reduction in time from 180 minutes to 90 minutes (Alamoudi, M, and Alamoudi, R.H., 2019).
Lean concepts applied in the workplace can also affect work safety. However, solutions implemented should be reviewed as well as existing standards for improvement.
By improving efficiency and standardizing procedures, your company can create a less hazardous and more predictable workplace environment. Technologies such as AI and IoT can further enhance the area of safety with lean manufacturing, smart manufacturing, and Industry 4.0 on the rise, by providing real-time data, automated safety interventions, and predictive analytics.
While visiting a motor shop recently, I noticed a sign to remind personnel in the shop of the “7 Wastes” of Lean, only this list only listed six of the seven wastes. I re-read it and counted again just to make sure, and I was correct; there were only six listed. Taking the lean methodology into account, all seven wastes are important, and that is how I came up with the idea to write this paper and its focus.
Among the best-accepted concepts in the pursuit of process improvement are: (1) lean, defined as elimination of waste, and (2) kaizen events as the dominant way to achieve lean and continuous improvement. (Schonberger, 2008) Lean methodology emphasizes eliminating waste to create more value for customers.
There are a number of lean tools that are used in reliability (Kaizen, JIT, Kanban, Values Stream Mapping, Etc.).
The Seven Wastes That Undermine Maintenance
One of the foundational principles of lean is identifying and reducing the “7 Wastes” which are activities that consume resources but don’t add value:
Overproduction
Collecting or analyzing more data than necessary or running tests and inspections more often than required. This ties up resources, creates excess inventory, and can potentially mask process inefficiencies. This is often one of the worst of the seven wastes, which can lead to waste such as inventory, waiting, and transportation.
Examples of Overproduction: Producing long reports with excess detail that will not benefit stakeholders in decision making, running condition monitoring on equipment daily when weekly checks are sufficient, producing additional parts/products when less have been ordered, which leads to storage and obsolescence.
Strategies for Elimination: Making the shift from time-based to reliability-centered maintenance (RCM) or condition-based, applying another lean tool (Pareto analysis) on failures, targeting only critical tasks, and using failure data analytics to eliminate unnecessary checks.
Overprocessing
Using non-user-friendly/complex tools, methods, and/or procedures beyond what’s required to achieve reliable performance. This consumes extra resources without improving the outcome.
Examples of Overprocessing: Performing full finite element analysis (FEA) when a standard reliability model would be beneficial, running excessive lubrication schedules “to be on the safe side,” which can essentially harm equipment, polishing hidden surfaces of parts that the customers will never see, and the addition of unnecessary precision in measurements.
Strategies for Elimination: Automating reporting through Computerized Maintenance Management Systems (CMMS) integration, standardization of maintenance documentation templates, and defining clear acceptance criteria so inspections stop at “fit for purpose”.
Overproduction and overprocessing are a waste of analytical resources.
Waiting
Delays in maintenance, repairs, or analysis that leave assets idle or technicians unproductive. Costs still accrue while nothing of value is being created.
Examples of Waiting: technicians waiting on spare parts and equipment before completing a preventive maintenance task, waiting for production downtime windows to run tests, which delays root cause analysis, waiting days/weeks for approval or bug fixes before being able to proceed.
Strategies for Elimination: The use of planned maintenance scheduling, applying predictive maintenance (PdM) scheduling work at optimal times, cross-training personnel to eliminate one staff person waiting on another to complete minor tasks.
Transportation
The unnecessary movement of tools, equipment or parts between sites of facilities which adds time, cost, and risk of damage without increasing value which adds cost, time and risk of damage without increasing value.
Examples of Transportation: Shipping failed components out for root cause analysis when in-house testing would suffice, moving spare parts repeatedly among locations due to poor inventory management.
Strategies for Elimination: Standardize toolkits for common maintenance tasks, usage of shadow boards or mobile maintenance carts to reduce searching and walking, and implementation of point-of-use storage near critical equipment.
Motion
The unnecessary movement by personnel during maintenance, inspections, or testing, which creates inefficiency, fatigue, and risk of injury.
Examples of Motion: Personnel walking long distances or reaching far across benches or for tools and equipment. Technicians walking across large plants multiple times for calibration equipment instead of using mobile kits. Searching through multiple unorganized databases to find past failure reports.
Strategies for Elimination: Designing ergonomic workstations, including frequently used items within reach, digital work instructions electronically stored in offices, and the use of IoT sensors to reduce manual checking of equipment.
Waiting, Transport, and Motion waste personnel, technicians, and engineers’ time.
Inventory
Excess raw materials, work-in-progress, or finished goods not being used. Also, holding too many spare parts, tools, or test samples that aren’t needed immediately. This ties up cash flow and storage space, potentially leading to spoilage or obsolescence. This waste is often overlooked.
Examples of Inventory: Stockpiling rare spare parts “just in case” without assessing criticality, which ties up capital in unused assets, maintaining calibration tools or outdated ones that will never be deployed, but still take up shelf space.
Strategies for Elimination: The use of Computerized Maintenance Management Systems (CMMS) to track usage and reordering, and adopting Just-In-Time (JIT) supply for items that are not critical.
Defects
Failures, rework, or misdiagnoses that require additional effort and reduce asset availability, errors, mistakes, or rework that require correction. Defects cost time, materials, resources, and damage customer trust.
Examples of Defects: Calibration errors on sensors that generate misleading data, forcing repeat testing and wasted downtime, incorrect root cause analysis leading to repeated failures, and incorrect data.
Strategies for Elimination: Applying Standard Operating Procedures (SOPs) for consistent repair quality, the use of root cause analysis (RCA) to prevent recurrence, implementing training and certification to reduce technician errors, and implementing precision maintenance practices such as torque, lubrication, and alignment.
Inventory and Defects directly impact uptime, cost, and trust.
I have come across an additional waste while researching this topic more; however, in obtaining my Lean Six Sigma Green Belt Certification, the Project Management Academy, through which I’m certified, focused on only seven. The additional waste, which is occasionally included as an eighth, is:
Skills/Unused Talent – Not utilizing people’s creativity, skills, or knowledge, which results in missed opportunities for problem solving, innovation, and improvement.
Examples of Skills/Unused Talent: Workers on the frontline are not requested for input on process improvement, having insights first-hand, personnel with strong data analysis skills working on repetitive/manual tasks rather than automation.
Strategies for Eliminating Waste in Reliability Programs
Now that the seven wastes have been identified, what is the tool to reduce these wastes? Lean refers to this as a Gemba Walk. Gemba is Japanese for “the real place”. This is a workplace walk-through in which leadership goes to the physical location to observe “where the action is”. It is important for leadership to know what they’re looking for, be focused on processes, make observations, and ask questions such as why, what, and why not by engaging with employees. This is a time when waste and opportunities are identified, and processes can be made more efficient or safer. The most important part of all of this is that overall improvements are made and followed up on to ensure success for the company.
References
Alamoudi, M. and Alamoudi, R.H. (2019) Implementing Lean Methodology in a Power Cable Factory: A Case Study of a Low Voltage Cable. American Journal of Industrial and Business Management, 9, 2083-2097. https://doi.org/10.4236/ajibm.2019.912138
Gomaa, A. H. (2025). Enhancing shutdown maintenance performance using Lean Six Sigma case study. International Journal of Lean Six Sigma. https://doi.org/10.1108/ijlss-03-2024-0043
Pérez-Naranjo, M.E., Avilés-Sacoto, S.V., Mosquera-Recalde, G.E. (2021). Lean Manufacturing Implementation in Management of Residues from Automotive Industry—Case Study. In: García Alcaraz, J.L., Sánchez-Ramírez, C., Gil López, A.J. (eds) Techniques, Tools and Methodologies Applied to Quality Assurance in Manufacturing. Springer, Cham. https://doi.org/10.1007/978-3-030-69314-5_17
Schonberger, Richard J. (2008). Best Practices in Lean Six Sigma Process Improvement – A Deeper Look. John Wiley & Sons Incorporated
Sumi, S. S. (2024). Innovative paths to productivity: Advancing lean manufacturing in industrial engineering. World Journal of Advanced Research and Reviews, 22(3), 176-184.
Teich ST, Faddoul FF. Lean management-the journey from Toyota to Healthcare. Rambam Maimonides Med J. 2013 Apr 30;4(2): e0007. doi: 10.5041/RMMJ.10107. PMID: 23908857; PMCID: PMC3678835.
