Last batch of highlights from Robert Glass's book.

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## Quotes from Robert Glass: Facts and Fallacies of Software Engineering ##
## Highlights from Robert Glass: Facts and Fallacies of Software Engineering ##
My favorite bytes from the wonderful book [Facts and Fallacies of Software Engineering](https://www.goodreads.com/book/show/83792.Facts_and_Fallacies_of_Software_Engineering) By [Robert Glass](http://www.robertlglass.com/)
@ -102,5 +102,35 @@ Software Reuse](https://www.cc.gatech.edu/~beki/c16.pdf)
* So what's the fallacy here? That quality is a management job. Management, of course, does have a vitally important role in achieving quality. They can establish a culture in which the task of achieving quality is given high priority. They can remove barriers that prevent technologists from instituting quality. They can hire quality people, by far the best way of achieving product quality. And they can get out of the way of those quality people, once the barriers are down and the culture is established, and let them do what they have wanted to do all along—build something they can be proud of.
* What's the alternative to an ego-invested programmer? A team-player programmer.
* Programmers really do need to be open to critique; the fact that we cannot write error-free programs, hammered home so many times in this book, means that programmers will always have to face up to their technical foibles and frailties.
* A system that works will have to acknowledge fundamental human traits and work within the bounds they create. And ego is one of those traits.
* **See also** Weinberg, Gerald. 1971. The Psychology of Computer Programming.
* There are sure a lot of people in the software world who would like to believe that one size fits all. Those selling methodologies. Those defining process approaches. Those pushing tools and techniques. Those hoping to build component-based software. Those setting standards. Those doing research toward the next software engineering holy grail. Those academics who put the prefix meta- in front of whatever they're working on. All of them are seeking that "universal software elixir." Many of them even believe they have found it. All too many of them want to sell it to you!
* Because software tackles such a diverse assortment of problems, it is becoming more and more obvious that there are few, if any, universal solution approaches. What works for business application programs will never be enough for critical, real-time software projects. What works for systems programming is often irrelevant to the needs of scientific applications. What works for small projects, and that includes today's Agile Development approaches, won't work well for those huge projects that consume hundreds of programmers. What works for straightforward projects will fail miserably if applied to critical projects.
* We are just beginning, in our field, to appreciate how diverse the problems we need to solve really are.
* Criticality matters. If lives or vast sums of money are involved in a project, you will treat it far differently—especially its reliability needs—than if they are not.
* Most practitioners are well aware that "my project is different." All too many theorists, however, disdain such a comment and see that practitioner as simply unwilling to try new (and often "universal") things (but see Glass 2002a).
* "The most interesting paradigm shift now taking place" in the field is "the shift away from the notion that all software is essentially the same."
* **See also** McBreen, Pete. 2002. Software Craftsmanship. Boston: Addison-Wesley. Contains a section explicitly titled One Size Does Not Fit All.
* **See also** Cockburn, Alistair. 2002. Agile Software Development. Boston: Addison-Wesley. Glass, Robert L. 2002a. "Listen to Programmers Who Say 'But Our Project is Different.'" The Practical Programmer. Communications of the ACM.
* **See also** The Loyal Opposition. IEEE Software. Glass, Robert L., and Östen Oskarsson. 1996. An ISO Approach to Building Quality Software. Upper Saddle River, NJ: Prentice-Hall. Highsmith, Jim. 2002.
* **See also** Plauger, P.J. 1994. Programming on Purpose. Englewood Cliffs, NJ: Prentice-Hall.
* **See also** Vessey, Iris, and Robert L. Glass. 1998. "Strong vs. Weak Approaches to Systems Development." Communications of the ACM, Apr.
* **See also** Yourdon, Ed. 1995. "Pastists and Futurists: Taking Stock at Mid-Decade." Guerrilla Programmer, Jan.
* No one is talking about inventing more methodologies, but everyone seems to be doing it.
* Almost no software practitioners are using these methodologies straight out of the box. On the contrary, most people who use a methodology adapt it to fit the situation at hand.
* **See also** Wiegers, Karl. 1998. "Read My Lips: No New Models!" IEEE Software,
* Because one program's LOC may be very different from another program's LOC: Is one line of COBOL code the same degree of complexity as one line of C++ code? Is one line of a deeply mathematical scientific application comparable to one line of a business system? Is one line of a junior programmer's code equivalent to one line from your best programmer? (See Fact 2 about those individual differences— upto 28 to 1—for an answer to that question.) Is one LOC in a heavily commented program comparable to a LOC in one with no comments? What, in fact, constitutes a LOC?
* Random test input is a good way to optimize testing.
* Via statistics-driven testing, software people can say things like "this product runs successfully 97.6 percent of the time." That's a pretty potent kind of statement to make to users. It's certainly more meaningful to those users than "this product has met 99.2 percent of its requirements" (that sounds impressive, but we already know that 100 percent requirements-driven testing is far from sufficient) or "this product has had 94.3 percent of its structure tested" (the typical user has no idea what "structure" is).
* The depth or shallowness of an error is unrelated to the number of people searching for it;
* Research on inspections suggests that the increase in the number of bugs found diminishes rapidly as the number of inspectors rises;
* The research on software inspections shows that there is a maximum number of useful inspection participants, beyond which the success of an inspection falls off rapidly (see, for example, Fact 37). And that number is quite finite—somewhere in the range of two to four.
* To build a replacement requires a source of the requirements that match the current version of the product, and those requirements probably don't exist anywhere. They're not in the documentation because it wasn't kept up to date. They're not to be found from the original customers or users or developers because those folks are long gone (for the average software product that has been around for a substantial period of time).
* The problem is this: In learning any other language, the first thing we do is learn to read it. You get a copy of Dick and Jane or War and Peace or something somewhere in between, and you read. You don't expect to write your own version of Dick and Jane or War and Peace until you've read lots of other examples of what skilled writers have written. (Believe me, writing Dick and Jane does require skill! You have to write using a vocabulary that's age- and skill-appropriate for your readers.)
* The problem is, we in the software world don't always agree on what good code or bad code is. Furthermore, most programs don't consist of just good or bad code—they contain a mixture of both.
* In spite of the fact that most programmers think that they're the best in the world at their craft, I think we have to admit that the War and Peace of software has not yet been written!
* The only time we in software tend to read code is during maintenance. Maintenance is a much disdained activity. One of the reasons for that is that code reading is a very difficult activity. It is much more fun to write new code of your own creation than to read old code of someone else's creation.
* Programmers at Work. Redmond, WA: Microsoft Press Contains this quote from a then younger Bill Gates: "[T]he best way to prepare [to be a programmer] is to write programs and to study great programs that other people have written.
* The complexity of the software process and product drives a lot of what we know and do in the field. Complexity is inevitable; we shouldn't fight it, so much as learn how to work with it. Fifteen of these facts are concerned with complexity, and a number of others are driven by it.
* Reality is the murder of a beautiful theory by a gang of ugly facts.
* And I would suggest that practitioners considering some tool, technique, method, or methodology that is at odds with one or more of these facts should beware of serious pitfalls in what they are about to embark on.