Is there a name for this phenomenon?
It happened to me this morning when I was having trouble with the Hub printer. Boss comes over, wants to know what’s taking me so long, I explain it’s the printer and not me, and he punches the same exact command sequence I did six times in a row and it works FINE for him.
Make me look bad, dammit.
When the revolution comes, that computer’s going outside on the lawn for an “Office Space” beat-down, I tell you.
“NFF” (No Fault Found) is one standard description of this not-at-all-uncommon phenomenon.
A technician might say something like “We’re getting a lot of NFF’s on the fourth floor - maybe there’s something wrong with the power there.”
I call it “self-healing.” Sometimes, I have wondered if the machines aren’t just biding their time, waiting for the right moment to take over the world. 
intermittent fault
PEBKAC - Problem exists between keyboard and chair.
An apparent wetware problem.
Keyboard driver fault.
On a more serious, technical side, NFF (described above) and intermittent are terms that might be used.
Short between floor and keyboard.
ID-10-T error. (take out the dashes).
I have had plenty of times when I tried something 4-6 times, then doublechecked and found something stupid like i used a \ instead of a / or { instead of [ on a command line. Happens to everyone.
FNF (Fault Not Found) or RWT (Right When Tested) are the two we use in the telephone service.
Sheesh, so many answers, and not a one of them relevant. What you experienced is called the observer effect.
You do something eight times and it never works. You call someone over to help you. You say “why doesn’t this work?” and do what you did eight times before, and now it works. The observer effect.
You reset a machine a couple of times. Kick it a little. Give up and call a repairman. Repairman pushes on button, and now it works. The observer effect.
And shame on all who refered to “PEBCAK” and ID-10-T problems. The observer effect will mock you soon enough.
Serendickity.
Not exactly what the OP is asking for. You are describing a malfunction caused by user error. The OP is talking about when your car makes that horrible squeaking noise everytime you turn left but when you take it to the shop you can’t make it do the same thing to save your life. Then it does it again as soon as you get home.
The same phenomenon happens with children, fevers and doctor’s offices. My pediatrician claims if she could market her waiting room chairs as miracle fever reducers, she’d put Children’s Tylenol right out of business.
I’ve seen that example used in context of Murphy’s law.
Being a Murphy myself, I am all too familiar with his interpretations of the law. You’d think he’d give family members a break, but noooooooooooo!!!
I always called them a PFM repair (Pure freekin Magic, or it’s derivatives).
You’re all wrong. The real name is “Pain in the Ass” and it’s the most common mode of equipment failure in my experience.
With automobiles the only solution is to keep running the thing until it fails for good. This usually happens about halfway between Trona and Death Valley. On July 15th. At 2 o’clock in the afternoon.
I find it is usually called “$60 service charge.” :smack:
As an ex-repairman, it used to happen to me all the time, and I would put it down to my “magic touch”. Annoying, 'cos I didn’t used to charge for NFFs, and it takes a certain amount of time to ascertain that the thing’s working correctly. Sometimes I’d find something wrong, only to discover it’s a design fault, and they’re all like that.
Nowadays I always keep a shitty stick handy in case there’s someone with faulty electronic equipment approaching and they need beating.
Sometimes it’s user error, sometimes the fault is intermittent (something common with dirty electrical contacts or dry solder joints), and sometimes the fault will self-clear (like a strand of wire causing a short circuit falling off in transport to the repair shop).
I drive an old Citroen. I save up all the random and intermittent faults, and then take a deep breath and tackle them all in one go.
A related issue is when you have an error that fails to show up when you try to run any sort of test or diagnostic, but shows up reliably when you don’t.
In my line of work, these bugs are often the result of timing issues, so when you run with debugging output on or under a debugger, the timing changes and the bug disappears. These are, for obvious reasons, a serious bitch to find and fix.
We call them “Heisenbugs.”
A co-worker used to refer to bugs which were impossible to replicate in front of your colleagues as “singing frogs”, from the old Looney Tunes cartoon.
Thanks for all the replies.
We may have a winner with “Singing Frogs.”
In software, they’re called heisenbugs.