Why does setting the hard-limit for maxfiles to "unlimited" using `launchctl limit` result in a hard-limit slightly above the soft-limit?

>Why does setting the hard-limit for maxfiles to "unlimited" using launchctl limit result in a hard-limit slightly above the soft-limit? By setting the maxfiles limit using launchctl to launchctl limit maxfiles 10000 unlimited, I get the following result: nlykkei-mbp:~ nlykkei$ launchctl limit maxfiles maxfiles 10000 10240 Initially, after the system has booted, hard-limit is set to "unlimited", so why can't I set the same hard-limit by setting it manually?