One mantra of the sysadmin arts imparted by my sensei many, many moons ago: "Anything with moving parts is evil." RS-232 is _full_ of moving parts.
What is the sound of one handshaking? USB-to-serial converters that... don't.
The states of "enlightenment" and "dejected resignation" are one.
#PERQ sufferers, from novitiate to master, take heed; this is as far as I go with shameless self-promotion: