This seems to be a common enough occurrence that it would merit its own phrase. I imagine it might be some sort of subset of Murphy's Law. But it's specific enough that Murphy's Law doesn't quite address it.

Do you know when you are banging your head against a wall for hours trying to fix something? And then when you finally give up and try to get someone else to come fix it (or even just look at it to see that it's broken), it's working perfectly as if nothing had ever happened? And at this point, you're just trying to convince the other person that it was broken in the first place.

It'd at least take some of the frustration out of the experience if you could both just laugh about <insert the phrase for it here>. But as it is now, I basically have to go through the whole paragraph above to say it, and at that point the joke is kind of lost.

  • I'd describe it as an 'unfortunate coincidence!
    – user66974
    Commented Mar 11, 2015 at 7:39
  • The boy who cries wolf ;-)
    – ScotM
    Commented Mar 11, 2015 at 7:59
  • 1
    It is kind of odd that, while this situation appears with fair regularity, there is no common term for it. I think I've maybe heard "immaculate correction" once, but that's about it.
    – Hot Licks
    Commented Mar 27, 2017 at 4:09
  • mistaken perception: You think something is broken when it isn't. And I don't think you are looking for computer or IT lingo, are you??
    – Lambie
    Commented Apr 26, 2018 at 15:50

10 Answers 10


In my office we call this a proximity fix, as the only thing necessary to fix the issue is to be near it: we stand behind the user and everything magically works. These days we can remotely control workstations, but still the fault disappears just by the act of attempting to observe it.

They are certainly the easiest tickets to fix.

  • 3
    That's perfect. How about even Schrödinger's fix with your description of "just the act of attempting to observe it" fixes it?
    – cchapman
    Commented Mar 12, 2015 at 11:46
  • 1
    But that would only work if it was both broken and not broken beforehand. I think yours works better for what I was originally describing
    – cchapman
    Commented Mar 12, 2015 at 11:50
  • I had a client who had a finicky Mac network in the 90s, one that would go down every few days. When I'd come to fix it the moment the elevator I was in reached their floor, boom, it started working perfectly. After the third or fourth time it became downright spooky. Definitely a proximity fix, very useful. Commented Apr 4, 2015 at 3:41
  • 1
    Related concept: rubber ducking.
    – user86291
    Commented Apr 5, 2015 at 11:14
  • How does this answer relate to the question? I don't see it. In the OP's question, the person believing something was broken had a mistaken perception of the situation....
    – Lambie
    Commented Apr 26, 2018 at 15:51

I believe what you are trying to explain is the observer effect.

In science, the term observer effect refers to changes that the act of observation will make on a phenomenon being observed. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner.



This is a little different to your question since the problem doesn't magically fix itself, but the solution does magically come to you through nothing more than another person hearing you describe the problem:

In programming this can be known as 'rubber ducking'. Where just by describing the problem to someone you come up with the solution, without them having to say a word (usually due to the effort of framing the problem as a question you realise something you've missed etc)

So-called since the same effect can often be procured by explaining the problem to an inanimate object i.e. a rubber duck sitting on your desk.

It's always a pleasure to be the rubber duck because you don't have to say a word, it often doesn't even affect your flow state, but your colleague goes away happy!





This certainly warrants the expansion of - @#+$! I had it right here. Where did it go?

The vanishing act:

to go away, usually because you do not want to do something or meet someone:

Surely the problem doesn't want to meet anyone who can solve it. That's why it hangs around me, right!?


What you have is an intermittent fault in what must thus be regarded as an item of unreliable equipment.

You might then wish to think of the device as exhibiting repair phobia or deficiency shyness.


One professionally used term for intermittent problems that vanish every time you try to analyze them is "Heisenbugs".

  • +1 I for the right idea and cool pun keshlam :) However if you check my answer link you will see that Heisenberg's Uncertainty Principle is often mistaken for the Observer Effect for this instance.
    – Neil
    Commented Apr 6, 2015 at 1:47
  • Granted, but as I said Heisenbug. however incorrect, is a well estimated term in science and engineering.
    – keshlam
    Commented Apr 6, 2015 at 4:14
  • The Observer Effect is when you use the debugger or connect an oscilloscope and the problem goes away. A Heisenbug is when you ask a colleague to look at what is going wrong and the problem just goes away without you doing anything.
    – user184130
    Commented Aug 18, 2018 at 14:17

I think Vorführeffekt (got that from QI's twitter feed) would be a good match - while not English I reckon we get to nick it by dint of being a Germanic language!

  • I edited your question, this part I'm trying to find the opposite - the code that works fine until you try to demonstrate it! should really be another question. I removed it to prevent your answer from being downvoted or removed, feel free to ask it as a question (provided you give an example of how you use it in a sentence).
    – JJJ
    Commented Apr 26, 2018 at 15:49

immaculate correction

It's from one of those lists, words that should be but aren't. Yet

  • 3
    Nice first answer here on English.Stackexchange. You can improve it by adding formatting to bold and/or quote your answer to make it more clear. Also, consider adding context for how it is used in a sentence. Commented Feb 9, 2016 at 3:25
  • 1
    Please give a proper explanation of how to use the phrase. Commented Feb 9, 2016 at 10:25

While "intermittent fault" is probably the best technical term, when I worked in tech support, we'd refer to them as "phantom bugs" or "phantom errors", since they were like ghosts: never around when you tried to analyze them, only showing up when they couldn't be recorded/proved/examined.


You thinking "placebo effect," although referring to a machine...its giving a patient a fake remedy, so that the mental state thinks it got the remedy it needs..yet there was nothing wrong with the patient at all. Same refers to machines that don't want to work...yet you grab a screw driver and shazaam..it works.

  • 1
    Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.
    – Community Bot
    Commented Jun 18, 2023 at 15:29

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.