The AIAG established the MSA, 4th Edition, as an international guideline to determine if the selected measurement system is capable and can be used for the intended purpose. The MSA guideline provides a practical basis for decision-making and is applied in both scientific and industrial contexts. In addition to the MSA, the Guide to the Expression of Uncertainty in Measurement (GUM) has standardized the determination of measurement uncertainties at an international level. This paper provides a practical example of using a surface comparator to demonstrate the limitations of the MSA for roughness parameters. Additionally, it presents a new method for assessing the capability of a measuring system for roughness measurements by considering the aspects from MSA and GUM. This work considers all information, distinguishing between existing and experimentally generated data. The experimental investigations for the application of the new method were carried out using a confocal laser scanning measuring microscope. The approach presents a new practical opportunity for both science and industry.