First, the user forms a conceptual intention from her/his goal. Second, s/he tries to adapt this intention to the commands
provided by the system and from these commands carries out the action. Then, the user attempts to understand the outcomes
of her/his actions. This is particularly important for computer systems, where the inner workings are hidden and users
have to figure out the internal state only from few hints. The last three stages help the user to develop her/his idea of the
system. The whole process is performed in a cycle of actions and evaluation. The user refines the model of the system s/
he has in mind by interpreting the outcome of her/his actions. (Marinilli 2002)