1 00:00:00,350 --> 00:00:03,610 These issues and difficulties can result in requirements 2 00:00:03,610 --> 00:00:06,780 that show various problems. Two particularly relevant and 3 00:00:06,780 --> 00:00:10,880 common problems are completeness and pertinence. Or better, 4 00:00:10,880 --> 00:00:14,750 the lack of completeness and pertinence. Completeness refers to 5 00:00:14,750 --> 00:00:17,560 the fact that it is often extremely difficult 6 00:00:17,560 --> 00:00:20,370 to identify all of the requirements. That is it 7 00:00:20,370 --> 00:00:22,890 is very difficult to have a complete picture 8 00:00:22,890 --> 00:00:25,780 of the purpose of the software. So what happens 9 00:00:25,780 --> 00:00:28,540 is that incomplete requirements are collected and the software 10 00:00:28,540 --> 00:00:32,500 is missing functionality that is important for the user. Pertinence 11 00:00:32,500 --> 00:00:34,720 conversely has to do with the relevance of the 12 00:00:34,720 --> 00:00:38,770 requirements. To avoid completeness problems developers often end up collecting 13 00:00:38,770 --> 00:00:42,640 a lot of irrelevant when not conflicting requirements. In 14 00:00:42,640 --> 00:00:45,060 these cases what can happen is that the software could 15 00:00:45,060 --> 00:00:47,120 either end up being bloated that is it might 16 00:00:47,120 --> 00:00:51,290 contain a needed functionality. The functionality represented by these extra 17 00:00:51,290 --> 00:00:54,120 requirements or it might even be impossible to build the 18 00:00:54,120 --> 00:00:57,480 software due to the conflicting additional requirements. And to make 19 00:00:57,480 --> 00:01:00,920 things even worse collecting all of these requirements sometimes doesn't 20 00:01:00,920 --> 00:01:03,390 even solve the completeness issue. So you might end up 21 00:01:03,390 --> 00:01:05,800 with a set of requirements that is not only incomplete 22 00:01:05,800 --> 00:01:08,740 but it also contains extra information that can be harmful 23 00:01:08,740 --> 00:01:11,450 to the system. So again the bottom line is that 24 00:01:11,450 --> 00:01:14,310 gathering an adequate, accurate, complete, 25 00:01:14,310 --> 00:01:16,500 and pertinent set of requirements that 26 00:01:16,500 --> 00:01:20,100 identify the purpose of a software system is an arduous task.