What is a Model - Based on Jurgen Appelo's Lecture

• A model is a miniature representation of something.
• It is a description or analogy that helps us to visualise something we cannot directly observe
• A system of postulates, data, and inferences presented as a mathematical description of an entity or state of affairs.

There are two types of models

Confirmatory Models: Used for Prediction and Control -- cannot use them in complexity context. 

Exploratory Models: Insight & Understanding [Sense making].

There is only ONE criterion for a Model -- Does the Model help me Make Sense of the world? (Insight and understanding)

How detailed / rigorous should a model be?

Usefulness of a model depends on the complexity of the person's mind (analysing the problem) and the environment / situation (context) within which they find themselves.

Simple and Complicated Models

[Prince 2 Process :-) ]

Note: Models are never perfect. Usefulness is context-dependent. It depends on the people and environment. (My interpretation -- therefore it is very important to understand whether the Agile framework you are recommending (Scrum / Kanban / or another) really aligns with the product development / project you are working on).