## 2 Theoretical Background
### Qualitative Methods  
In the analysis of different qualitative methods, several contributions are considered. [PERSON] et al. [11] present a framework in which a Delphi panel was conducted to assess the future environment and business trends with consequences for industrial PMM. The Delphi panel helps build a framework to understand the implications of how industrial PMM systems are designed and used. Firstly, it is necessary to understand better the strategy design and implementation process, particularly the link with PMM and how they should be combined to best suit such environments. The process is structured as follows: a questionnaire is submitted to the Delphi panel; the answers are sorted into a table where the number of solutions for each questionnaire item is listed; then, aware of the step mentioned above, a framework is developed that must explain the relationships between the strategy and the industrial PMM system (e.g., by implementing the so-called 'Performance Alignment Matrix' that reflects the complexity encountered by organizations). This paper points out that a qualitative methodology can, at the same time, be easy to apply, inclusive of internal and external perspectives, and ultimately successful in assessing the consistency of a tree of indicators. Unfortunately, it suffers from the fact that it has a static recalculation frequency and lacks an accurate comparison of the company's KPIs. In the contribution by [PERSON] et al. [12], an algorithm for analyzing questionnaire responses, the so-called Enterprise Analysis Model (EAM), is proposed. It is a tool that makes it possible to perform the analysis of the enterprise within a reasonable timeframe. The model helps to identify business weaknesses and provides information on the data that should be collected to change the situation shortly [13]. The model was used to gather company information by applying mapping and questionnaires, which can be merged into a single survey. Expert decision-making and outlier methods can reduce the number of KPIs to several meaningful metrics. Subsequently, data analysis is performed based on the response analysis algorithm. This methodology, therefore, considers parameters such as dynamicity in recalculation frequency, evaluation of KPIs, comparison of performance indicators, and inclusion of internal/external perspectives. However, this approach consists of an algorithm whose complexity must be considered when implementing it. In the contribution proposed by [PERSON] et al. [14], a performance alignment matrix and the Cynefin framework is proposed. The research approach adopted here was to consider theory alongside empirical data collection; this research uses theoretical sampling rather than statistical or random sampling. For the method implementation, interviews are conducted on how performance is measured in the company and what decisions are based on. Since Cynefin is a framework that tries to make sense of what it analyzes, it addresses both predictable and unpredictable external contexts characterized by complexity and volatility and also offers insights into the complexity of an industrial PMM. The acquisition of performance data is intended to enable managers to make decisions. The qualitative method provided by [PERSON] et al. [14] provides a very dynamic structure based on considerations made between experts in a Cynefin session, which makes the approach emotional and well inclined to look at the external perspectives of companies. However, it should be noted that although it is a method of low application complexity, it consists of an empirical study, which may lead to distortions as it is not practical and only theorized. [PERSON] et al. [15] evaluated the effects of the performance measurement system using two sets of variables:  
1. Managers' responses regarding their satisfaction with the industrial PMM;
2. Publicly available information on company accounting and stock market performance. The proposed model is based on questionnaires submitted to managers.