Expectation: "Oh, this deployment is not properly configured yet, we have to solve this before going in production."
Reality: "Well, it's does what the requirement said, we have no time at hand and I would need to learn how to configure that properly, so let's just go in production and solve this later on." [Later on never happens]
This is way to common. Entire setups "YOLOed" because people have no idea how to do things properly. It highlights how important well automated (self-)services are.
@sheogorath and then there's the "unknown unknowns", where people go into production with so little information that they do not even understand what they are doing wrong or which corners they are cutting.
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