What is the most interesting defect you've encountered?

Discussions
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1

I’m curious to know what people’s most interesting and insightful defects have been?

I am not looking for your favourite “I was great for catching this” bug, but one that made you really stop and think.

Some examples from me:

  • Our new feature had horrible behaviours with a specific appliance that had a limited (but turned up to 11) feature set. We didn’t know or consider that it existed. This led to new questions early in projects going forward!
  • A minor package uptick on an embedded control led to a crash with certain devices that weren’t compatible. “Upticking as good practice” became a wider conversation.
  • A poor design choice in handling connection startup led to network storms. I learnt a lot about network protocols that day (although my memory of the specifics of the bug is fuzzy).
2

As a performance tester my testing scope is limited, however I do remember one application where the performance was actually slower when there was low traffic. We could test it at full volumes and it was perfectly fine (and so passed it’s exit criteria), but it turned out things went to sleep a bit too quick so performance at low volumes was awful. Now I pay attention to ‘low’ and ‘normal’ as well as ‘peak’.