Why are images copied with relative file paths rather than using absolute file paths?

If I open a file outside the Lettera folder, and add images, those images are referenced in the file with relative file paths and are copied to the folder containing the text file. Why is this? There’s nothing good about copying files rather than using absolute file paths. If you edit the original images, you need to re-add them to the file or you forget that the updates aren’t reflected.