iTunes users opting not to allow the program to automatically keep their folders organized (the default setting) may be well aware that iTunes does not respond well after changing locations of or renaming files. In fact, any change in the file name or path renders the item inaccessible from within iTunes, almost as if your iTunes library disappeared. To make matters worse, there's no easy way to have iTunes relocate files moved. iTunes prompts the user to relocate missing files but only one at a time with a dialog that says:
The [type] [name] could not be used because the original file could not be found. Would you like to locate it?
Not so useful when a lot of files are moved at once. But if a directory containing hundreds of files needs to be moved, to a larger hard drive for example, locating files individually becomes too much work.