A diagram is not a model: The huge difference between them
A diagram is not a model. Some people may argue, but lack of an understanding about the differences between these two kinds of representations can lead to undesirable situations.
A diagram is just a perspective from a model. You can understand this better by thinking about a 3-D model of a house and the several perspectives or drawings that can be extracted from that 3-D model.
In some cases, you can work backwards and build a 3-D model from several perspectives. You can even hide the view of the model completely, but it will still be there.
This is very different from having many perspectives of something without having anything as a foundation—as the source of truth for these perspectives. This is what a model primarily is—a foundation.
At first, it seems to be easier to work in a simple diagram-centric paradigm because you can just start drawing freely and are not constrained by anything. It also seems easier because you do not have the burden of defining the underlying infrastructure of the model: the meta-model, something that is not necessarily difficult, but may not be a trivial task either. Customizing a meta-model to address your specific needs is something that most users should do, but I will not be discussing that aspect of modeling in this blog post.
To avoid having to construct the infrastructure of the model yourself, in some cases you can get one that is ready for immediate use like the Unified Modeling Language (UML). You could also use one of the meta-models that comes with IBM
To move from an easy-to-start diagram-centric environment to a more complex model-centric environment, you should see value in all or some of the following points:
So, despite the fact that starting your work in a diagram-centric environment may initially seem faster and simpler, the model-centric capabilities mentioned above and used by systems engineering are one key to successfully building smarter products.
Are you working more with a diagram or are you taking a model-centric approach?