Well over half of the time you spend working on a project (on the order of 70 percent) is spent thinking, and no tool, no matter how advanced, can think for you. Consequently, even if a tool did everything except the thinking for you - if it wrote 100 percent of the code, wrote 100 percent of the documentation, did 100 percent of the testing, burned the CD-ROMs, put them in boxes, and mailed them to your customers - the best you could hope for would be a 30 percent improvement in productivity. In order to do better than that, you have to change the way you think.
Fred BrooksMore software projects have gone awry for lack of calendar time than for all other causes combined.
Fred BrooksThe hardest part of the software task is arriving at a complete and consistent specification, and much of the essence of building a program is in fact the debugging of the specification.
Fred BrooksEinstein repeatedly argued that there must be simplified explanations of nature, because God is not capricious or arbitrary. No such faith comforts the software engineer.
Fred BrooksThe boss must first distinguish between action information and status information. He must discipline himself not to act on problems his managers can solve, and never to act on problems when he is explicitly reviewing status.
Fred BrooksThe first step toward the management of disease was replacement of demon theories and humours theories by the germ theory. That very step, the beginning of hope, in itself dashed all hopes of magical solutions. It told workers that progress would be made stepwise, at great effort, and that a persistent, unremitting care would have to be paid to a discipline of cleanliness. So it is with software engineering today.
Fred Brooks