Towards the end of the practice of hanging that is. The earliest stuff was barbaric with people just being choked to death for minutes.
The 'long drop, short stop' method was better, if calculated right. Then you'd have your neck and spine snapped killing you instantly.
I think out of all the non-chemical based executions, guillotine is probably one of the least barbaric. A weighted razer sharp blade falling at speed onto the neck is quick, precise and efficient. There's little chance of the blade failing to cut or any chance of it missing, as with a headsman with an axe or sword. Your victim is going to be executed painlessly, and die instantly, compared to hanging or electric chair where they may take some time to die and be in considerable pain. And the guillotine can easily be reset for another person. At most the headblock may have to be changed, compared to gallows/ropes needing to be designed for each user if it's to be efficient.
If anything, guillotines only downside is being messy.
contrary to popular belief, the guillotine is actually painful for about 15 to 30 seconds as it has been studied by observing the severed heads for the short time they are conscious upon being separated from the body (though this occurrence of being conscious is rare).
Guillotine was mostly done away with for this pain but for also how symbolically barbaric it has become. It's an extremely messy business and because of that it just seemed cruel to people who have any moral fibers in their body. The practice of decapitation of the head is a massive statement too as its an attack on ones very visage.
A huge number of different components are packed into our heads. The human head contains more than 20 bones, up to 32 teeth, a large brain, of course, and several sensory organs, as well as dozens of muscles, and numerous glands, nerves, veins, arteries and ligaments. They are all tightly configured and intensely integrated within a small space. And people’s heads look good too. The human head boasts one of the most expressive set of muscles known to life. It is adorned with various features that lend themselves to ornamentation: hair, ears, nose and lips. Thanks to an impressive concentration of nerve endings and an unrivalled ability for expressive movement, our heads connect our inner selves to the outer world more intensely than any other part of our body. And its set upon a pedestal for all to see. ~ Frances Larson
strangely enough personally if i were to pick how i died i feel that decapitation would be one of the ways i'd pick. The concept and practice of the severing of the head is something that fascinates me to a high degree.