Prompt quality does matter, but at some point context side does matter.
I’ve had thing like a system that has a collection of procedural systems. I would say “replace the following set of defaults that are passed all around for system X (list of files) and in the managed (file) by a config” and it would do that but I’d suddenly see it be like “wait mu and projection distance are also present in system Y and Z. Let me replace that by a config too with the same values”. When system Y and Z uses a different set of optimized values, and that was clearly outside of the scope.
Never had that kind of mistakes happen when dealing with small contexts, but with larger contexts (multiple files, long “thinking” sequences) it does happen sometimes.
Definitely some times when I though “oh well my bad, I should have clarified NOT to also change that other part”, all the while thinking that no human would have thought to change both