tackable office chairs is not a reflection of the concept of system design
Strictly speaking, the "stackable office chairs" is the concept of architecture design, not the concept of system design, because it is not strictly functional requirements.
Narrowly speaking, system design is through demand and conceptual analysis, outline design, detailed design, to achieve the function of the system. The main function of the chair is "for people to sit."
Stackable, belonging to the system of non-functional requirements, personal opinion it is equivalent to a system performance requirements, so that the chair can be stored in a small area, or can be regarded as a flexible demand, that scalability requirement, is to sit A feature enhancement and expansion. This non-functional requirements are achieved through architectural design.
You can imagine the sliding design of the sliding door, it also belongs to the category of architectural design, not the scope of system design.
Of course, there is a perception that architecture design is a part of system design, and of course non-functional requirements can be included in this broad system design, so that stackability can also be used as a concept for system design. But I firmly do not advocate this! Because this will make the design becomes unclear, or even ignore a lot of non-functional requirements, lost a lot of architectural innovation opportunities.
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