The remaining work to finish in order to reach your goal increases as the deadline approaches.
Adding manpower to a late software project makes it later.
When all else fails, read the instructions.
Every task takes twice as long as you think it will take. If you double the time you think it will take, it will actually take four times as long.
There is always one item on the screen menu that is mislabeled and should read "ABANDON HOPE ALL YE WHO ENTER HERE."
Dr. Caligari's Come-Back
A bad sector disk error occurs only after you've done several hours of work without performing a backup.
- To study an application best, understand it thoroughly before you start.
- Always keep a record of data. It indicates you've been working.
- Always draw your curves, then plot the reading.
- In case of doubt, make it sound convincing.
- Program results should always be reproducible. They should all fail in the same way.
- Do not believe in miracles. Rely on them.
Blessed is the end user who expects nothing, for he/she will not be disappointed.
Gilb's Law of Unreliability
- At the source of every error which is blamed on the computer you will find at least two human errors, including the error of blaming it on the computer.
- Any system which depends on human reliability is unreliable.
- Undetectable errors are infinite in variety, in contrast to detectable errors, which by definition are limited.
- Investment in reliability will increase until it exceeds the probable cost of errors, or until someone insists on getting some useful work done.
The amount of expertise varies in inverse proportion to the number of statements understood by the general public.
Harp's Corollary to Estridge's Law
Your "IBM PC-compatible" computer grows more incompatible with every passing moment.
The first myth of management is that it exists.
Hind's Law of Computer Programming
- Any given program, when running, is obsolete.
- If a program is useful, it will have to be changed.
- If a program is useless, it will have to be documented.
- Any given program will expand to fill all available memory.
- The value of a program is proportional to the weight of its output.
- Program complexity grows until it exceeds the capability of the programmer who must maintain it.
- Make it possible for programmers to write programs in English, and you will find that programmers cannot write in English.
Hoare's Law of Large Programs
Inside every large program is a small program struggling to get out.
The Last One's Law of Program Generators
A program generator creates programs that are more "buggy" than the program generator.
There's never time to do it right, but always time to do it over.
Murphy's Fourth Law
If there is a possibility of several things going wrong, the one that will cause the most damage will be the one to go wrong.
Murphy's Law of Thermodynamics.
Things get worse under pressure.
Ninety-Ninety Rule of Project Schedule
The first ninety percent of the task takes ninety percent of the time, and the last ten percent takes the other ninety percent.
The man who can smile when things go wrong has thought of someone he can blame it on.
An ounce of image is worth a pound of performance.
Variables won't constants aren't.
O'Toole's Commentary on Murphy's Law
Murphy was an optimist.
The solution to a problem changes the problem.
Rhode's Corollary to Hoare's Law
Inside every complex and unworkable program is a useful routine struggling to to be free.
Robert E. Lee's Truce
Judgement comes from experience; experience comes from poor judgement.
It works better if you plug it in.
Build a system that even a fool can use, and only a fool will want to use it.
- Given any problem containing N equations, there will be N+1 unknown.
- An object or bit of information most needed will be least available.
- Any device requiring service or adjustment will be least accessible.
- Interchangeable device's won't.
- In any human endeavor, once you have exhausted all possibilities and fail, there will be one solution, simple and obvious, highly visible to everyone else.
- Badness comes in waves.
Thoreau's Theories of Adaptation
- After months of training and you finally understand all of a program's commands, a revised version of the program arrives with an all-new command structure.
- After designing a useful routine that gets around a familiar "bug" in the system, the system is revised, the "bug" is taken away, and you're left with a useless routine.
- Efforts in improving a program's "user friendliness" invariably lead to work in improving user's "computer literacy." That's not a "bug," that's a feature!
An expert is a person who avoids the small errors while sweeping on to the grand fallacy.
As soon as a still-to-be-finished computer task becomes a life-or-death situation, the power fails.
Zymurgy's First Law of Evolving System Dynamics
Once you open a can of worms, the only way to recan them is to use a larger can.