It's cold-hearted, but if scale is an issue, then some of the alternatives can seem equally horrifying. Is it really more humane to send a couple of axe-wielding Bobs to the office, set them up in one or two rooms, and then steadily parade people in and out over the course of a day, the rest of the team trembling and gossiping and worrying about when and whether their turns will come up, their eyes locked on every colleague and friend to slink back to his desk from the abattoir?

Think about that at 1,000-person-layoff scale. If we apply some basic Little's Law math to the process here, we quickly see how "by-hand" firings would drag on for quite some time, perhaps needlessly prolonging the inevitable, and almost certainly disrupting work at the entire office for days on end.

There is no "good" way to do this. I've never had to do it myself, and I can only hope I never have to. The thought of how "best" to do it would keep me up for weeks. At the very least, I suppose in-person messengers are better than automated voicemail recordings, or sealed envelopes. But even if using a human messenger, a mass layoff is not going to go down well for the people being laid off. There is something to be said for ripping off the band-aid (though perhaps in timed batches, so you're not just dumping N people out into the cold, to fight over the same jobs on the market all at once).