Term or expression which best describes a problem that goes away when an expert attempts to diagnose it?

There is a phenomenon which I've seen happen across many circumstances. Generally, it goes something like this:

1. The complainant has a recurring observable problem.


2. The complainant contacts an expert who may be capable of solving that problem.


3. When the complainant attempts to reproduce the problem while the expert is present, the problem is no longer apparent. The expert never witnesses the problem.


4. The problem may or may not occur again after the expert goes away.

I'm wondering if there is a term or expression that best describes this phenomenon.

I'm also curious if this is the correct forum for such a question, because the answer I'm looking for doesn't necessarily have to be in English. For example, it could be something like schadenfreude, which may or may not have a simple English counterpart (although in that case, Wikipedia suggests the expression Roman holiday).

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