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<p class="MsoNormal">PBL >> <i><span style="font-size:10.5pt;color:black">“Requirements specification is an unsolved engineering problem, and is likely to remain so for quite a while (if not for ever).”</span></i><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;color:black">ST > I would disagree, personally. Software requirements can be specified precisely, concisely, etc.<o:p></o:p></span></p>
<p class="MsoNormal">It depends on the definition of “requirements”. There are no end to stories of software that met its requirements, which was not fit for purpose.<o:p></o:p></p>
<p class="MsoNormal">One major problem is completeness (in breadth and depth).<o:p></o:p></p>
<p class="MsoNormal">I would lay down a bet that a substantial number of post mortems (particularly in security and safety-critical CPSs) would have the developers saying: “If we’d only known…”. Generally, these statements can’t be completed by “… we would
have written the software differently” without also including “we would have written the requirements differently”.<o:p></o:p></p>
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