Name = Ying and Yang pattern

I first noticed this problem when I was working as a quality control person in a feed mill.  I noticed that when something got out of whack, it showed itself in at least two places.  I also noticed that any one anomaly could be caused by any number of things, but a pair was generally caused by a limited number of possible causes.

Problem = Identifying the cause of things that have gotten out of balance in a closed system can be difficult to do from outside the system.  A closed system being broadly described as a system where the inputs and outputs are well known and measured.

Solution = Anomalies within a closed system express themselves in more than one way.  Look for pairs of anomalies with well defined and limited sets of possible causes.

Consequences =  Since pairs of anomalies have smaller sets of possible causes, you can check the possible causes quickly and facilitate a correction quicker.
-----
This sounds plausible.  But can anybody give an example?
It seems to me that it is the examples that are the
pattern, not YingAndYang.

-RalphJohnson