Similarly to the way matrix #1 was discovered it is possible to ask: which entity's life-cycle is implemented by the enterprise? The obvious answer is that it is the products (services) produced by the enterprise.
In fact many attempts to implement the integrated information flow in the enterprise have been based on Integrated Product Models. The question arises, then, how does enterprise engineering - as an integrating factor - relate to product-model-based integration?
With the introduction of the Product Life-Cycle Matrix it is now clear that the enterprise model should be such (including the requirements, design, detailed design and building and operating the enterprise) that it implements the full product life-cycle.
By looking at the product life-cycle matrix the enterprise engineer can derive a full set of requirements for the enterprise designed. In fact the knowledge of the product life-cycle is a prerequisite of the successful enterprise engineering process.
The Product Life-Cycle Matrix (matrix #4) should be defined and disseminated together with the Generic Enterprise Reference Architecture and Methodology. Furthermore, matrix #4 would allow to compare product modelling languages and their scopes (e.g. STEP [11]), showing the connection with the product life-cycle, and with the enterprise life-cycle.
As an important result, this approach unifies product model-based and enterprise engineering-based integration.