It's easy to forget that the entire point of the method was that it was considered humane; the alternative execution method for French nobility was usually getting their heads chopped off with a sword or ax, which sometimes took several painful whacks. And commoners just got hanged, which sucked even harder. So even though we imagine that the walk to the guillotine was pretty nerve-racking, getting your head lopped off in one swift blow was mercifully brief compared to the torturous alternatives.
That's not to say that the French Revolution's Reign of Terror, which ended with over 16,000 heads, is up for a retroactive Amnesty International award for employing a relatively mild form of capital punishment. But hey, at least they weren't 16,000 disembowelments. And it's all ancient history anyway -- in a world where most countries have done away with executions completely, beheadings have to be the stuff of the powdered wig era.
Most of history was just folks passing time, waiting for the Internet to be invented.
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