- Simpler and cleaner overall file system layout, with full compatibility.
- Clear separation of operating system and host specific resources.
- Improve compatibility with other Unixes/linux, no confusion about tools install locations, no $PATH fiddling, all possible paths to a binary will always work. All binaries will be available on both /usr and / thus minimizing compatibility problems.
- Improve compatibility with build systems such as GNU autotools who never have been aware of the /usr split in the first place
- Minimize difference to other Unixes, such as Solaris, which already did the same move
- Isolate the vendor-supplied mostly read-only operating system resources from the rest, thus allow snapshotting of the OS, and easy lightweight container OS duplication