The user interface must be intuitive even for average computer users.

The user interface must be clean, which means for example, the right-click menu should only contain the basic operations for a file manager, and should not be cluttered with confusing and useless options such as Create tarball or Create ISO.

Just like Terminal, the file manager should feature a high degree of maintainability, using OO design techniques and GObject implementation features. Maintainability goes over Performance.

This point goes hand in hand with the maintainability. Minimum required platforms are GNU/Linux (esp. Xfld), FreeBSD, NetBSD and Solaris.

File manager should be fully standard compliant. It doesn’t buy us anything if we invent our own wheels.

File manager needs to be fast (startup time, directory load time, responsiveness). Fitness for the LiveCD scenario (see Terminal and xfdesktop-ng for examples how to achieve this).

The file manager needs to be fully accessible using Assitive Technologies.