Process for System Architecture and Requirements Engineering Quotes

“Ask residents of Manhattan what functions the city provides for them, and they will give you an impressive list. Do this for all the various stakeholders in the city, and you will have a pretty good set of requirements for Manhattan. This would be a useful exercise for city planners or for anyone considering starting a business in the city. In summary, then, the fact that not all systems are requirements-driven does not diminish the value of analyzing requirements. Whether we carry out the analysis before or after the system exists, it still has great benefits.”
― Derek Hatley, Process for System Architecture and Requirements Engineering

“The point is best made by stating that not all systems are requirements-driven, at least, not driven by formal written requirements of the kind we have described so far [Rechtin 97]. As an example: A city is a people-made system, but (with a few notable exceptions) no one actually sits down and writes a set of requirements for a city, and then builds it. Rather, cities evolve over time, starting as small settlements exploiting favorable locations or natural resources, and growing as new facilities are added and more people decide to move in. It is most unlikely that the original settlers on Manhattan Island ever dreamed what their creation would grow into!”
― Derek Hatley, Process for System Architecture and Requirements Engineering

“These needs, then, are just as real as any other requirements; we refer to them here as required constraints or design constraints, and they are a very important part of the whole requirements set.”
― Derek Hatley, Process for System Architecture and Requirements Engineering