If we want to solve a technical problem, a first step is to create a mathematical model of the underlying real system. It is a matter of experience to identify the essential parameters of that system and come up with a model that is as simple as possible, but nevertheless adequately reflects reality.
Sometimes standard models from textbooks will do. Other tasks demand adaptation, refinement, partial re-modelling or suitable combination of existing models.
In this phase, it is paramount that I work in close contact with my customers in order to completely understand the problem and to ensure a correct, adequate model. In particular, "implicit" assumptions (obvious to the expert in the field) must be made explicit. Mistakes at this stage often can be corrected only at the price of a complete re-start.
In the modelling phase in particular, broad experience and thoroughly pondering alternatives is essential. CMM is supported by the wide expertise of its partners to find the best solution.