A word for careful detail once had a much more disagreeable range.
Latin fastidium named disgust or aversion, behind fastidiosus and English fastidious. Older English could use the adjective for something disgusting or disagreeable. Its common modern use concerns meticulous attention.
Source
Merriam-Webster: fastidiousWord History gives fastidium, disgust; the edited usage discussion explicitly documents older disgusting/disagreeable senses and modern meticulous usage.