What's the difference between auto-mount and permanent on Virtualbox

When adding a shared folder on a running VM, "Auto-mount" will mount the folder immediately but the mount will not stick after reboot. "Make Permanent" makes automount VirtualBox shared folder persistent (sticks on reboot).

I usually check them both if I wish a shared folder to be always available.

The "Auto-Mount" will be executed first after reboot of guest OS while the "Make Permanent" shall share folders in a running guest OS.