The competence level model
... is a model from developmental psychology and, like all models or constructs of reality, is actually wrong. Let's take a brief look at the basics of model building: A model in the scientific sense is a representation of reality. It is always incomplete, usually greatly simplified or distorted in order to be able to concentrate on essential aspects. Modeling is primarily about abstraction, because reality is too complex to represent it completely.
With regard to snow and avalanche science and the human basics that play into the profession, models help immensely to present difficult and highly complex facts in a simple way in order to understand situations or to raise the imagination to the next level. In most cases, however, the models themselves are wrong and have to be "deleted" afterwards as soon as they have fulfilled their purpose in order to enable further development steps first - but not to hinder them in the future. One example here is the widespread idea of the "ball bearing" in connection with weak layers in the snowpack: No weak layer functions like a ball bearing, because the descent of slab avalanches is about fractures, not about snow layers that are completely unbound - as would be the case with a ball bearing. Weak layers are "weak in binding", not "without binding", and simply break apart more easily - they don't roll through the area. Nevertheless, the ball bearing was a good, simple "model" to give a complete newcomer to the topic something they could grasp and to help their imagination.
In practice, the following classifications in the competence level model interlock completely seamlessly or flow into each other - but they still help with imagination.