Of course 30s is a bit too long.
Just don't use! I never use My Document folder! Use whatever other folder instead. Because it is the default, many program save, delete, save and delete inside, might cause the file structure to act abnormally. Just don't use! Like wise, I don't use default My Picture, My Music etc. Silly folder structures. Of course, I am the only one who uses that PC. Shared PC is more troublesome.