File names sometimes change during duplication to prevent conflicts when the new file would otherwise share the same name and location as an existing file. Operating systems enforce uniqueness within a single folder, as two files cannot have the identical full path (like 'Documents/Report.docx'). Duplication tools automatically rename the copy to avoid accidentally overwriting the original file.

For example, if you copy a file named 'Vacation.jpg' within the same folder using Windows or macOS, the duplicate might become 'Vacation - Copy.jpg' or 'Vacation(1).jpg'. Similarly, if you duplicate a project document named 'Budget.xlsx' and save it in the same directory without providing a new name, the system will typically append a version number to create 'Budget (1).xlsx'.

This automated renaming prevents critical data loss through unintentional overwrites, serving as an important safeguard. However, the resulting names can sometimes seem arbitrary or inconsistent, requiring manual cleanup later. The specific renaming convention (like using 'Copy' or incrementing numbers) depends on the operating system or application used. This behavior is fundamental to data integrity across all file systems.