This might be worth expanding…
Doctor Strange Rule
Put the warning before the spell. Digital context? Do like the gov.uk design system folks and put the guidance before the sample code (so perhaps developers will read it!). Don’t do like some other design systems and put the guidance after the code.
In email, no one can see you smile
Sometimes, it’s better to light-up a video chat or share a meal, rather than exchange soulless corporate paragraphs.
Just as stories for kids often work better with just one “moral of the story,” it’s often better to focus on a single message. This works in blog posts, speeches, etc. Too many “points” to the story and some of it invariably gets lost.
Just because you’re “in charge,” doesn’t mean you should ignore your developers when it comes to picking a launch date.
League of Legends Rule
Be sure that your demo of how to do one thing doesn’t teach students to do another thing very poorly.
One early LOL demo showed new players how to move their character (“champion”) around the playing field, how to shoot & slay monsters (“minions”), how to earn gold and spend it on items. In the example, the new player would purchase (if memory serves) thornmail armor for their archer (Ashe). This was generally considered a silly idea for gameplay and a poor example to present to new players.
How about a non-gaming example? Let’s never use “password” as the password in a demo on how to use a login system. Someone’s going to follow that example — and that can’t be a good thing. Always set a good example, especially if you’re not going to explain why a bad example is a bad example. N00bs are n00bish. Roll with it.
Minimally Viable Products Must be Viable
Even an MVP needs to do enough right to be useful. I’m reminded of a certain DC-based whiz-kid dev group that published a universal log-in system that lacked 2FA when it was already a necessity for their customers. “It’s just an MVP” isn’t/wasn’t a viable excuse.
Works on My Box
A “Works on my box” problem occurs when a designer or developer fails to account for real customers and creates a web product that looks/works fine on their hardware/software combo, but not for folks in the real world.