Laughter is provoked by a discontinuation of what your brain expects.

If you saw a dog walking a man on all fours, you would most likely laugh, because of the unexpectedness.

In this case, the unexpected terseness causes laughter. You don't expect what follows to just be "Eject". In a technical context like a manual, you expect what follows to be a detailed list of steps and instructions. When this expectation is shattered, you laugh.

Thanks for reading. Have a good day.

Speaking of humour, I can't tell what I find funnier: the fact that someone didn't see how these checklist items could possibly be construed as humorous, or your clinically precise explanation of the concept of humour itself, complete with a mechanistic explanation and example. Together, they're a beautiful example of the tone of HN.

Thank you. This is my first time on HN actually, and I was captivated by the same tone you speak of. Are you interested in chess?

Everyone says they're funny because they're unexpected, but simple direction and plain language is exactly what I'd expect from an aviation checklist, so I have no idea.

It's not just they're unexpected. They're both expected and unexpected. You also expect a manual to have details. It's the sudden ending that is both fitting and not fitting that creates the humour shock.

It's funny. That's it. People just find it funny.

I guess I don't really get that then - it's funny that someone designed it sensibly? Not sure where the joke is.

I originally downvoted both your comments, but after a few seconds of reflection realized that it's not deserved, and undowned both.

I think you _truly_ are missing the point of why it's funny, and that's fine. Humour is a pretty subjective thing in the end.

Yes! The standard is so senseless that something sensible is hilarious.

In a mad world, a sane man is considered mad.

Don't worry, it's just humour being subjective.