In the face of global competition and rapid technological development, businesses are forced to look for ways to improve their efficiency and reduce costs. One of the most recognized and effective approaches to achieving these goals is the concept of Lean Manufacturing, or “lean production”. First developed and applied in Japanese automobile companies such as Toyota, this methodology has quickly gained popularity around the world due to its ability to significantly improve manufacturing processes and results [1].

Lean Manufacturing focuses on eliminating all types of losses (muda) in the production process, including excess inventory, excessive motion, waiting, defects, and other inefficiencies. The basic principle is to create maximum value for the customer while minimizing resource inputs. This is achieved through continuous improvement (kaizen) and the active involvement of all employees in the optimization process.

Lean Manufacturing is a management concept aimed at improving the efficiency of production processes and creating maximum value for the customer with minimum resource inputs. The main goal of lean manufacturing is the elimination of all types of losses and continuous improvement of work processes.

The basic principles of lean manufacturing are:

Define Value: Value is defined from the perspective of the end user. This is the first and most important principle of lean manufacturing. It is necessary to understand what the customer considers valuable in a product or service. Anything that does not add value from the customer’s perspective is considered a loss and must be eliminated.

Identify the Value Stream (Map the Value Stream): This principle involves analyzing all the steps required to create a product or service, from the initial stage to delivery to the end customer. The goal is to identify and eliminate all types of losses in the process.

Create Flow: Once losses have been identified and eliminated, it is necessary to organize processes so that they flow continuously and without delays. This helps to reduce production time and increase flexibility.

Introduction of the Establish Pull system: An Establish Pull system means that production starts only when there is a customer order. This helps to avoid overproduction and reduces inventory. Using Kanban system where production of a new product starts only after receiving a signal that the previous product has been used or sold.

Improvement (Pursue Perfection). Lean manufacturing requires a constant pursuit of excellence through continuous improvement. This means that all employees must be involved in the process of finding and eliminating losses. Implementing a Kaizen culture where employees regularly suggest ideas for process improvements and participate in their implementation [2].

Lean manufacturing is based on minimizing losses in production. Losses are anything that does not add value but increases the cost of the product or service being produced. Losses are divided into explicit and hidden. In this concept there are 8 main types of losses:

Overproduction. Overproduction is dangerous because it leads to other types of losses. However, it is the easiest to spot. In manufacturing plants, overproduction means making more products than the customer requires. This can be caused by incorrect demand forecasts and a desire to fully utilize production capacity. In an office environment, overproduction can manifest itself in the form of creating reports that take up more than half of work time, drawn-out meetings, or preparing presentations that may not be needed. The main causes of this phenomenon include inefficiently configured work processes, complex hierarchies and excessive bureaucratization of work.

Excess Inventory. Stockouts occur due to overproduction or ordering large quantities of parts. Stocking up on products eats up money for warehouse rent and staff salaries. It is especially dangerous to stockpile products with a fast shelf life. In office work, overstocks are dozens of simultaneously opened documents and programs, and piles of incoming mail.

Incomplete production. Downtime of personnel and equipment due to approvals, parts failures, slow document flow, and inconsistencies between departments can lead to a situation where, over time, this problem will cause a piece of work to become irrelevant and may never be completed.

Improper logistics. This is the movement of parts and finished products over greater distances than necessary. For example, if the warehouse and production are far apart, the products will cost more than if the production and warehouse are in the same building. Additional risks can include transportation defects, equipment wear and tear, and late carriers. Improper logistics in the office — this is the forwarding of paper documents, unnecessary movements during approvals and so on.

Scrap. This type of loss includes the cost of correcting defects, disposing of irreparable rejects and quality checks on products. Scrap happens due to complex technology, worker error and poor quality materials. Defects also exist in office work. For example, a misspelled letter, a poor design option, an unreadable document format.

Excessive processing. These are processes that do not add value to the product, but increase production costs. For example, a built-in monitor for refrigerators or excessive animation on a website. Excessive processing is done if they haven’t analyzed the market and understood what the customer needs.

Unnecessary movements. Losses occur when the workplace is not organized to meet the needs of the worker. For example, when you have to reach for a tool in a factory or drag a heavy part across the shop floor. Or when in an office you have to open a lot of folders to find the information you need. Even small unnecessary operations and movements have a cumulative effect on the scale of months or several years multiplied by the number of employees.

Mistakes in human resource management. These are losses from inefficient work. For example, when an employee performs a task he or she doesn’t know how to do and therefore spends more time on it. Or vice versa — the manager does the work of subordinates. His labor costs the company more, plus he may not have time to do his job [3].

Figure 1. The Six Big Losses in lean manufacturing

The development of a production system in a company will require the use of lean production tools. The toolkit of lean production in the modern world has more than 50 different possible solutions, but experts emphasize a few main ones that are most effectively used in industry.

The 5S system is one of the key methodologies of lean manufacturing, aimed at organizing and maintaining order in the workplace. It consists of five steps, each beginning with the letter “S” in Japanese.

The first step is Sort (Seiri), the purpose of which is to remove all unnecessary items from the workplace. Conduct an audit of all items and decide what is really needed to get the job done. All unnecessary items should be removed to free up space and reduce clutter. Examples include removing old documents, unnecessary tools and excess materials.

The second step is Set in Order (Seiton), which aims to organize the remaining items for easy access and use. Arrange all necessary items so that they are easily accessible and each item has a specific place. Use labeling, color codes, and other visual aids to make items easier to find and return to their place. Examples include setting up tool racks, labeling shelves and drawers, and creating layout diagrams.

The third stage is Shine (Seiso), which aims to clean and maintain a clean workplace on a regular basis. This includes regular cleaning of the workplace, equipment and tools to help maintain high standards of cleanliness and identify problems early. Examples include daily cleaning, regular equipment maintenance and checking the cleanliness of work areas.

The fourth step is Standardize (Seiketsu), the purpose of which is to establish standards for maintaining order and cleanliness. Develop standards and procedures to maintain the first three “S’s”. This may include checklists, cleaning schedules, and workplace organization guidelines. Examples include creating standard operating procedures (SOPs), cleaning checklists, and inspection schedules.

The fifth step is Self-Discipline (Sustain, Shitsuke), which aims to maintain and improve the processes in place. Ensure that standards are consistently met and encourage a culture of self-discipline among employees. Regular trainings and audits will help maintain a high level of 5S compliance. Examples include conducting regular training sessions for employees, conducting 5S audits and reward systems for compliance [5].

Implementing 5S into your work environment brings many benefits that contribute to overall efficiency and quality of work. One of the key benefits is improved productivity, achieved by making it easier to find and use tools and materials. This allows employees to find the items they need faster and minimize time spent preparing for work. Workplace safety is also greatly improved by keeping the workplace clean and organized. Eliminating unnecessary items and organizing space helps reduce the risk of injuries and accidents, making the work environment safer for all employees. The quality of work is improved through better organization of the workspace. When all items are in their places and easily accessible, there is less chance of errors and defects. This contributes to more accurate and higher quality task completion. In addition, the implementation of the 5S system has a positive impact on employee morale. A streamlined and clean work environment contributes to a better overall mood and increased employee satisfaction, which in turn can lead to increased motivation and productivity. Finally, the 5S system contributes to significant time savings. Reducing time spent searching for needed items and materials allows employees to focus on their tasks, which increases overall efficiency and reduces time spent on non-productive activities.

Also, Kanban system can be used to optimize enterprise management systems. Kanban means “signal, card” in Japanese. The cards visualize the tasks that are in progress. They help the team keep track of what is happening with the tasks, and if there are delays — immediately see at what stage.

A card can be physical (in the form of a sticker) or electronic. A sticker usually contains a minimum of data: the name of the task, the deadline and the name of the person responsible. An electronic card is more detailed — it collects all the information about the task and discusses it with colleagues. All these cards can be gathered into a single structure — a Kanban board. The Kanban board can be real — on a board with colorful stickers — or virtual — in a special application [6].

The Kanban system relies on several main aspects. These aspects shape the principles of work even in the most seemingly small processes within production.

Firstly, the visualization of work plays an important role. Kanban boards are used to visualize all tasks and the stages of their execution. This allows all process participants to see the current state of work, identify bottlenecks and promptly respond to emerging problems. Secondly, limiting work in progress (WIP — Work In Progress) helps to avoid overloading workers and resources. Limiting the number of tasks performed simultaneously helps to distribute the workload more evenly and improve the quality of task completion. The third principle is flow management. Constantly monitoring and optimizing the flow of tasks through all stages of the production process minimizes task completion time and eliminates delays. The fourth principle is the explicit definition of rules. Establishing clear rules and procedures for completing tasks, transitioning between stages, and resolving problems provides transparency and unambiguity in the performance of work. The fifth principle is the use of feedback loops. Regular meetings and discussions to analyze the current state of work, identify problems and find ways to solve them allow the team to continuously improve processes and adapt to changes. The sixth principle is collaborative improvement and evolution. Continually striving to improve processes and practices by involving everyone involved in the improvement process fosters a culture of continuous improvement and innovation. Finally, supply and demand balance is an important aspect of the Kanban system. It helps to balance production capacity with actual demand, avoiding overproduction and shortages of products. This is accomplished through the use of Kanban cards that signal the need to replenish inventory or start new work [7].

Figure 2. Example of a Kanban board

Applying these principles allows organizations to effectively manage production processes, reduce costs, improve product quality and increase customer satisfaction. The Kanban system promotes a flexible and adaptive production environment that can respond quickly to changes and market demands.

Total Productive Maintenance (TPM) is considered to be an equally important principle. The basis of this method is a certain approach to the maintenance of production equipment, aimed at the constant maintenance of its working condition. In essence, it is a concept describing the optimization of maintenance and its alignment with production goals. TPM is an important part of the more global concept of Lean Manufacturing.

In contrast to the conventional maintenance approach, where only the service department or a specially hired service company monitors the equipment, TPM involves line production personnel and employees of related departments in the process of regular maintenance. All of them become sources of information about the technical condition of devices, perform simple operations themselves and work out solutions to high-level problems that are sources of losses. They are also involved in improving the maintenance process itself. Such universal responsibility eliminates the classic conflict between production and service departments, when it is more profitable for the former to operate the equipment on wear and tear, and for the latter to stop processes for work. Instead, the TPM concept suggests that the service department should strive for equipment efficiency and the production department should strive to reduce downtime. TPM integrates preventive maintenance practices, involvement of all employees, and continuous process improvement to maximize equipment performance. The main aspects and principles of TPM include the following elements:

Autonomous Maintenance: Involvement of equipment operators in the daily maintenance and care of machines. This includes regular cleaning, lubrication, inspection and minor repairs. Operators become the first to notice any abnormalities or problems, allowing them to respond quickly and prevent serious breakdowns.

Planned Preventive Maintenance: Develop and execute maintenance plans based on equipment condition and operation. This includes regular inspections, parts replacements and preventive measures to prevent breakdowns and extend equipment life.

Staff training and development: Train operators and technicians in the skills required to effectively maintain and repair equipment. This improves employee competence and contributes to faster and better problem solving

Equipment Improvement: Continuous review and improvement of equipment and production processes. This may include modernizing equipment, improving working conditions and introducing new technologies to increase productivity and reliability.

Early Equipment Management: Incorporate TPM principles during the design and installation phases of new equipment. This helps avoid common problems and ensures a smoother transition to operations.

Quality of Service: Implementing systems and procedures to ensure high quality equipment maintenance and repair. This includes standardization of processes, use of quality parts and tools, and continuous quality control of work performed.

Safety and Environmental Protection: Attention to safety and environmental responsibility in the maintenance and operation of equipment. This includes complying with safety codes and standards, using environmentally friendly materials and technologies, and minimizing environmental impact.

Administrative and support services: Embedding TPM principles into administrative and support processes such as inventory management, logistics, planning and data management. This helps to create a holistic management system covering all aspects of production operations [8].

Implementing Total Productive Maintenance can significantly improve equipment efficiency and reliability, reduce repair and maintenance costs, improve product quality and increase customer satisfaction. TPM contributes to the creation of a culture of continuous improvement and the involvement of all employees in the process of achieving the company’s common goals.

Figure 3. Eight pillars of Total Productive Maintenance

Implementation of the lean production system is a voluminous task consisting of several main stages. The algorithm of the implementation work has been compiled so that it is possible to analyze in detail each stage of building this system, as well as to familiarize with possible improvements on the production part.

The first step is the preparatory stage, including analysis of current processes and employee training. A detailed analysis of all production processes allowed to identify existing problems and losses. At the same time, trainings and seminars were organized for all levels of personnel to familiarize them with the principles and methods of lean production. Next comes the identification of problems and losses. With the help of value stream mapping, maps of current processes can be created which helps in identifying all types of losses. Data analysis tools are typically used at this stage to identify key problem areas. Implementing the 5S system of sorting, ordering, cleanliness, standardization and discipline is also a significant step. Unnecessary items will be removed from workstations, remaining items will be organized for easy access, workstations should be cleaned regularly. In addition, standards for maintaining order should be developed and employees trained to maintain discipline.

A Kanban system is implemented to manage production flows and minimize work in progress. Visual cues and Kanban cards can help optimize flows and improve synchronization with customer needs. Continuous process improvement could be achieved through Kaizen. Working groups should regularly analyze and improve processes by implementing improvement suggestions from employees at all levels. Autonomous maintenance (Jidoka) can also be an important element. Employees are trained in the principles of autonomous maintenance and defect detection, and equipment is equipped with an automatic stop function when defects are detected. Just-In-Time (Just-In-Time) will optimize deliveries and production processes to minimize inventory and provide flexibility. This includes reviewing and optimizing the supply chain and adjusting production processes.

Finally, a great deal of attention should be paid to employee development. Regular training and development programs, as well as programs to motivate and involve employees in the improvement process, contribute to their professional growth and engagement [9].

The implementation of lean manufacturing can lead to significant reductions in production costs. This can be achieved by reducing various types of wastage such as excess production, excess inventory, unnecessary movements and waiting. Optimization of processes will allow for more efficient use of resources, resulting in lower operating costs. In addition, the implementation of Just-In-Time will minimize raw material and finished goods inventory, which has reduced storage and inventory management costs. As a result, the company will be able to significantly reduce overall production costs, which will have a positive impact on financial performance.

One of the key results of implementing lean manufacturing will be a significant improvement in product quality. The implementation of Jidoka principles will allow defects to be identified and eliminated at early stages of production, preventing them from accumulating and spreading further. Automatic systems for stopping production when defects are detected will provide an immediate response to problems, allowing them to be quickly rectified. Continuous process improvement through Kaizen helps to identify and eliminate the root causes of defects, which can lead to an overall improvement in product quality. As a result, scrap and returns are significantly reduced.

Optimization of workflows and implementation of the Kanban system has facilitated more efficient management of production flows and synchronization of operations. This should result in shorter cycle times and increased speed of order fulfillment. Employees are becoming more productive because their workstations have been organized according to 5S principles, which improves their working conditions and reduces the time spent searching for the necessary tools and materials. As a result, labor productivity can increase significantly. Improved product quality and shorter delivery times can have a positive impact on customer satisfaction.  Customers will start receiving products that meet their expectations and requirements, which will increase their loyalty and satisfaction. As a result, the manufacturing company will be able to attract new customers and retain existing ones, which has a positive impact on the company’s sales and market share.

Implementing lean manufacturing can also help to increase the flexibility and adaptability of the company to changes in the market. Developing employees through regular training and skill development programs helps to create a team that is ready to respond quickly to changes in demand and customer needs. Continuous process improvement (Kaizen) is able to ensure that changes in production processes can be made promptly, which allows any company to quickly adapt to new market conditions [10].

In conclusion, the implementation of Lean Manufacturing at enterprises clearly demonstrates that Lean Manufacturing is a powerful and versatile tool for minimizing losses and increasing efficiency. Application of its principles allows companies not only to reduce costs and optimize processes, but also to significantly improve product quality, which in turn leads to increased customer satisfaction and loyalty.

The experience of successful implementation of Lean Manufacturing confirms that companies, regardless of their industry and geographic location, can effectively apply global methodologies and approaches to achieve significant improvements. This includes not only the technical aspects of manufacturing, but also cultural changes within the company, such as engaging employees in continuous improvement and creating an atmosphere that fosters innovation and adaptability.

Thus, Lean Manufacturing not only helps businesses achieve short-term cost reduction and productivity goals, but also lays the foundation for long-term sustainable growth and development. This confirms that Lean Manufacturing is not just a set of tools and methods, but a holistic management philosophy capable of transforming a business and taking it to a new level of competitiveness and success.