Murphy was an optimist.
Just when you see the light at the end of the tunnel, the roof caves in.
Nothing is impossible for the man who doesn't have to do it himself.
In any computer system, the machine will always misinterpret, misconstrue, misprint, or not evaluate any math or subroutines or fail to print any output on at least the first run through.
When a compiler accepts a program without error on the first run, the program will not yield the desired output.
In nature, nothing is ever right. Therefore, if everything is going right... something is wrong.
Variables won't; constants aren't.
There's always one more bug.
If builders built buildings the way programmers wrote programs, then the first woodpecker that came along would destroy civilization.
The probability of anything happening is in inverse ratio to its desirability.
It works better if you plug it in.
It won't work.
Experience varies directly with equipment ruined.
Nothing ever gets built on schedule or within budget.
When working toward the solution of a problem, it always helps if you know the answer.
To estimate the time it takes to do a task: estimate the time you think it should take, multiply by two and change the unit of measure to the next highest unit. Thus, we allocate two days for a one hour task.
If it looks easy, it's tough. If it looks tough, it's damn near impossible.
Adding manpower to a late software makes it later.
Once a job is fouled up, anything done to improve it will only make it worse.
Whatever you did, That's what you planned.
Any inanimate object, regardless of its position, configuration or purpose, may be expected to perform at any time in a totally unexpected manner for reasons that are either entirely obscure or else completely mysterious.
prov. [Usenet]
"As a Usenet discussion grows longer, the probability of a comparison involving Nazis or Hitler approaches one."
There is a tradition in many groups that, once this occurs, that thread is over, and whoever mentioned the Nazis has automatically lost whatever argument was in progress. Godwin's Law thus practically guarantees the existence of an upper bound on thread length in those groups. However there is also a widely- recognized codicil that any intentional triggering of Godwin's Law in order to invoke its thread-ending effects will be unsuccessful.