## 2 Literature Review  
According to [6; 7; 8], two concepts can be encountered in the context of production optimization. The word loss was used, mainly, at the beginning of the last century after the First World War, and the word \"waste\" was not brought into practice until the 1970s. The biggest obstacle to increasing productivity is ignorance of waste, of any kind. The process is a series of consecutive steps that begins with the input of raw materials and ends with the output of finished products. Value is added to the product in each of the process steps. Workers and machines thus add value to the product, or do not add value. The term waste refers to all activities that do not add value to the product and, at the same time, increase the cost of the product [9; 10]. Waste is defined as activities that consume resources but do not create any value for the customer [11]. Most value-flowing activities that create value for the customer are a small part of all activities. Eliminating large amounts of waste has the greatest potential for improving performance [12]. Waste is anything that increases the cost of a product or service without increasing its value [13]. Through the gradual development of the concept of leanness, [PERSON] defined waste as 3 MU: MUDA--waste (time, material, resources), MURI--congestion (workers, lines, transport), MURA--non-continuity (work, supplies) [5; 8; 10]. MUDA (waste) is classified into today's seven categories:  
1. Overproduction--production of items for which there is no use. It is the worst form of waste because it contributes to the creation of another waste. 2. Supplies--in the form of raw materials, work in progress or finished products, represent capital expenditures that do not generate revenue for either the producer or the customer. 3. Waiting--arises when the work of workers stops. These are waiting for material, machine failures, the uneven workload of individual consecutive operations. 4. Transport--this is an unnecessary transfer of parts or products, such as from a warehouse processing step to a subsequent processing step, where the second step could be located immediately adjacent to the first step. 5. Movements--all unnecessary movements that workers must perform at work, e.g., search for tools, documents, etc. * Errors--these are inspections, rework of failures and scrap. * Overwork--performing unnecessary or incorrect processing, usually due to a bad tool or product design [14; 15; 16; 17; 18]. * Unused employee creativity--losses from not using ideas, skills, new improvements or learning opportunities [19]. The eighth type of waste was later added to this categorization. Today, in professional practice, waste from overproduction is considered waste according to the Toyota Production System [20]. Another way to classify waste is the 4M Ishikawa designation from 1950. The different types of waste are divided according to their origin: M = Man, M = Material, M = Machine, M = Method of work [21]. It is also possible to meet 5M, where the fifth component is added, M = Mother nature (temperature, humidity, etc.). According to [22; 23; 24], it is important to know the consequences for the overall production when defining waste. Recognizable consequences of waste include unused machines, work in progress, high stocks, overloaded workers, high error rates, ineligible processes, hazardous work, work in non-ergonomic working positions and conditions, complex material flows, and constant slippages in the plan. As reported by [25], production distinguishes two crucial dimensions of performance: quality and productivity. Productivity is then defined as the number of quality-compliant outputs produced per unit of each source (input) used. Quality is measured by the extent to which a product meets the specificities of its design. Continuously increasing productivity is one of the most important objectives of management.