When a fault is localized and the proximate cause is known but the systemic root is not, chain evidence-linked whys with a counterfactual stop and a countermeasure.
$npx -y skills add tjboudreaux/cc-thinking-skills --skill thinking-five-whys-plusInstalls into the current project.
Run `npx skills use "https://github.com/tjboudreaux/cc-thinking-skills" --skill "tjboudreaux/cc-thinking-skills/thinking-five-whys-plus"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/tjboudreaux/cc-thinking-skills" that are relevant to the current task. Run `npx skills add "https://github.com/tjboudreaux/cc-thinking-skills"` and select the relevant skills, then follow their instructions.