## 6 Verification of the Proposed Methodology
### Application Outputs  
One of the first values that we receive after data analysis is the overall average value of level of readiness of the entire area of internal logistics for the concept of Industry 4.0 across all the evaluated industrial enterprises. The value is 2.24 and it includes all the evaluated indicators. The core of the proposed methodology is a three-level structure of internal logistics, and average values of dimensions, sub-dimensions and indicators are also calculated. The average values of the five dimensions give the overall average value of readiness level. Given the scope of the resulting data, it is only possible to state without graphical form that the weakest analysed dimension for all the analysed industrial enterprises is dimension D3: Packaging (value 2.02). The best rated dimensions are D4: Supply (value 2.43). The remaining three dimensions have very similar values with minimal differences, and the values of the sub-dimensions also follow this pattern. Each sub-dimension consists of 3-4 indicators and is the most detailed output of the average values for all the enterprises. Logically, some indicators from dimension D3: Packaging have the lowest average value, specifically indicator I21: Degree of automation, I27: Attitude of the company to packaging management, and I29: Environmental aspects. Other sites that have a lower readiness level and are therefore potential sites for increased readiness are the areas in dimension D2: Storage, indicators I15: Material localizability and I18: Receipt and storage process. Lower values are also shown by all the indicators that relate to the environmental aspect of manipulation and storage technology, as well as information security, which appears in the fields of both manipulation and storage. The box plot in Figure 3 shows the characteristics of the set of values of the resulting coefficients using quartiles. Coefficient values correspond to level values. Minimum and maximum are the boundary lines, upper and lower quartiles are the edges of rectangles, the median is the line and the diameter is the cross. The value of coefficient 0.748 is the highest (only 1 company), for which the overall readiness of internal logistics was level 4. The average value of the coefficient for all companies is 0.448 (this corresponds to a value of 2.24). The analysed methodology outputs represent aggregated data that indicate only the average value of the level of readiness of internal logistics. Therefore, these average values were supplemented by the results of frequencies, i.e., number of occurrences of values within the analysed area. Figure 4 shows the total number of occurrences of the value of one of the levels for all evaluated companies for the entire area of internal logistics. The current level is shown in a bar graph, including regression curve interpolation. Level 2 (481 times) was most assigned during the input data collection and structured interview, followed by level 3 (396 times). As expected, the absolute minimum is level 5 and also level 0. This means that it is mainly a selection of lower levels. Level 4, already representing principles of Industry 4.0, contains only 138 assignments. Level 5 corresponding to full fulfilment of Industry 4.0 vision is practically non-existent. Figure 4: The number of occurrences of the current readiness level. Figure 3: Characteristics of set of coefficient values. Table 8 provides summary data on the results of the overall levels of the enterprises evaluated as a percentage. Out of the total of 29 companies, the largest representation according to the results is in three levels, i.e., in level 1, level 2 and level 3. The smallest percentage is in level 0, in which there are only two companies. The main idea for designing a zero level is not only to include it as the worst level, but for this level it is also the primary criterion that the internal logistics processes are not defined at all and are not managed. The minimum representation is in level 4, in which there is only one enterprise.