Fred Brooks Quotations

There is no single development, in either technology or management technique, which by itself promises even one order-of-magnitude improvement within a decade in productivity, in reliability, in simplicity.

Adding manpower to a late software project makes it later

How does a project get to be a year behind schedule? One day at a time.

How does a project get to be a year late? One day at a time.

The fundamental problem with program maintenance is that fixing a defect has a substantial (20-50 percent) chance of introducing another. So the whole process is two steps forward and one step back..

Systematically identity top designers as early as possible. The best are often not the most experienced.

Job Control Language is the worst programming language ever designed anywhere by anybody for any purpose.

Adjusting to the requirement for perfection is, I think, the most difficult part of learning to program.

Product procedure...must securely protect the crown jewels, but, equally important, it must eschew building high fences around the garbage cans.

Consensus processes starve innovative design by eating the resource.

Predictability and great design are not friends.

Men and months are interchangeable commodities only when a task can be partitioned among many workers with no communication among them.

But I will argue that knowing complete product requirements up front is a quite rare exception, not the norm.

I have never seen an experienced programmer who routinely made detailed flow charts before beginning to write programs.

More software projects have gone awry for lack of calendar time than for all other causes combined.

Study after study shows that the very best designers produce structures that are faster, smaller, simpler, clearer, and produced with less effort. The differences between the great and the average approach an order of magnitude.

The complexity of software is an essential property, not an accidental one. Hence, descriptions of a software entity that abstract away its complexity often abstracts away its essence.

The essence of a software entity is a construct of interlocking concepts: [...] I believe the hard part of building software to be the specification, design, and testing of this conceptual construct, not the labor of representing it and testing the fidelity of the representation.

Einstein argued that there must be simplified explanations of nature, because God is not capricious or arbitrary. No such faith comforts the software engineer.

Successful software always gets changed.

A design style is defined by a set of microdecisions. A clear style reflects a consistent set. A clear style may not be a good style; a muddled one never is.

Software work is the most complex that humanity has ever undertaken.

System debugging, like astronomy, has always been done chiefly at night.

Software and hardware design is less different than software designers think, but more different than hardware designers think.

Systems program building is an entropy-decreasing process, hence inherently metastable. Program maintenance is an entropy-increasing process, and even its most skillful execution only delays the subsidence of the system into unfixable obsolescence.

...when fits of creativity run strong, more than one programmer or writer has been known to abandon the desktop for the more spacious floor.

Improving your process won't move you from good to great design. It'll move you from bad to average.

When a task cannot be partitioned because of sequential constraints, the application of more effort has no effect on the schedule. The bearing of a child takes nine months, no matter how many women are assigned.

We tend to blame the physical media for most of our implementation difficulties; for the media are not "ours" in the way the ideas are, and our pride colors our judgement.

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.

Design work doesn't just satisfy requirements, it elicits them.

Dissertations are not finished; they are abandoned.

The critical thing about the design process is to identify your scarcest resource. Despite what you may think, that very often is not money. For example, in a NASA moon shot, money is abundant but lightness is scarce; every ounce of weight requires tons of material below. On the design of a beach vacation home, the limitation may be your ocean-front footage. You have to make sure your whole team understands what scarce resource you're optimizing.

Process improvement is most valuable in raising the floor of a community's practice.

The 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.

Scientists build to learn; Engineers learn to build.

The term architecture is used here to describe the attributes of a system as seen by the programmer, i.e., the conceptual structure and functional behavior, as distinct from the organization of the data flow and controls, the logical design, and the physical implementation. i. Additional details concerning the architecture

The programmer's primary weapon in the never-ending battle against slow system is to change the intramodular structure. Our first response should be to reorganize the modules' data structures.

All programmers are optimists. Perhaps this modern sorcery especially attracts those who believe in happy endings and fairy godmothers. Perhaps the hundreds of nitty frustrations drive away all but those who habitually focus on the end goal. Perhaps it is merely that computers are young, programmers are younger, and the young are always optimists.

A basic principle of data processing teaches the folly of trying to maintain independent files in synchonism.

A little retrospection shows that although many fine, useful software systems have been designed by committees and built as part of multipart projects, those software systems that have excited passionate fans are those that are the products of one or a few designing minds, great designers.

Plan to throw one (implementation) away; you will, anyhow.

The magic of myth and legend has come true in our time. One types the correct incantation on a keyboard, and a display screen comes to life, showing things that never were nor could be.... The computer resembles the magic of legend in this respect, too. If one character, one pause, of the incantation is not strictly in proper form, the magic doesn't work. Human beings are not accustomed to being perfect, and few areas of human activity demand it. Adjusting to the requirement for perfection is, I think, the most difficult part of learning to program.

Even the best planning is not so omniscient as to get it right the first time.

The 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.

One can expect the human race to continue attempting systems just within or just beyond our reach; and software systems are perhaps the most intricate and complex of man's handiworks. The management of this complex craft will demand our best use of new languages and systems, our best adaptation of proven engineering management methods, liberal doses of common sense, and a God-given humility to recognize our fallibility and limitations.

Conceptual integrity is the most important consideration in system design.

The management question, therefore, is not whether to build a pilot system and throw it away. You will do that. Hence plan to throw one away; you will, anyhow.

The Waterfall Model is wrong and harmful; we must outgrow it.

I am more convinced than ever. Conceptual integrity is central to product quality.

The programmer, like the poet, works only slightly removed from pure thought-stuff. He builds his castles in the air, from air, creating by exertion of the imagination. Few media of creation are so flexible, so easy to polish and rework, so readily capable of realizing grand conceptual structures.

Mediocre design provably wastes the world's resources, corrupts the environment, affects international competitiveness. Design is important.

The bearing of a child takes nine months, no matter how many women are assigned.

To only a fraction of the human race does God give the privilege of earning one's bread doing what one would have gladly pursued free, for passion.

A computer program is a message from a man to a machine. The rigidly marshaled syntax and the scrupulous definitions all exist to make intention clear to the dumb engine.

The hardest single part of building a software system is deciding precisely what to build.

A scientist builds in order to learn; an engineer learns in order to build.

The 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.

Originality is no excuse for ignorance.

Observe that for the programmer, as for the chef, the urgency of the patron may govern the scheduled completion of the task, but it cannot govern the actual completion. An omelette, promised in two minutes, may appear to be progressing nicely. But when it has not set in two minutes, the customer has two choices - wait or eat it raw. Software customers have had the same choices.

Present to inform, not to impress. If you inform, you will impress.

It is very difficult to make a vigorous, plausible, and job-risking defense of an estimate that is derived by no quantitative method, supported by little data, and certified chiefly by the hunches of the managers

System debugging has always been a graveyard-shift occupation, like astronomy.

An ancient adage warns, "Never go to sea with two chronometers; take one or three.

Show me your flowcharts and conceal your tables, and I shall continue to be mystified. Show me your tables, and I won't usually need your flowcharts; they'll be obvious.

Nine people can't make a baby in a month.

You can learn more from failure than success. In failure you're forced to find out what part did not work. But in success you can believe everything you did was great, when in fact some parts may not have worked at all. Failure forces you to face reality.