My LEGO(r) models, and definitely my Airfix(r) models were (largely) "static" - yes, they had wheels and propellers that turned, but otherwise they were constructions of parts that you looked at - hanging them on black cotton from the ceiling, pretending they were flying (Airfix planes I mean!).
And so, sadly it is with so many system models... Drawings of parts connected together... boxes and lines - "static views". Just like my childhood Airfix model, imagination is needed to try and work out what the parts of the construction might do, together and individually, and whether that was the right response to some requirement or other. How nieve, and how common - because it's easy...
...or at least easier than the alternative - accurately describing how the system reacts to an external event; its behaviour, drawn as "dynamic views". It's not as if we do not know how to create these views: all our methods provide notations for dynamic views, and some even state clearly how a dynamic view (or more often a set of dynamic views) relate to a corresponding static view.
Put otherwise, a system model described through a set of static views leaves a lot to chance, but is easy (and cheap). Only when the modeller invests in dynamic views can you be sure.
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