Why We Keep Making Bad Slides (Even When We Know Better)
You know the moment. The lights dim, the room hushes, the speaker clears their throat… and then it happens.
A wall of text.
Twelve bullet points.
Maybe a stock photo of a doctor wearing a white coat, though you've not worn one in years.
And the speaker apologises — “Sorry, I know this is a bit text-heavy, but I’ve got a lot to get through.”
Everyone smiles politely because we’ve all been here before.
We’ve all taken photos of slides we know we’ll never read again.
💡 ONE IDEA WELL
What fascinates me isn’t the bad slide itself.
It’s the fact that the speaker knows it’s not good practice… and they do it anyway.
This isn’t stupidity.
It’s not laziness.
It’s the gravitational pull of presentation culture — the deep, unexamined belief that this is how talks are done.
We inherit the rituals of the world we’re raised in.
Medical conferences. Grand rounds. Webinars.
Rows of chairs, podium at the front, and slides that function like public confession documents.
There’s comfort in the familiar.
Comfort in filling the slide, as if more words somehow reduce the chance of forgetting something important.
But here’s what the evidence keeps telling us — loudly, repeatedly, for more than 30 years:
1. Sweller’s Cognitive Load Theory (1988)
Our working memory is tiny.
Text-heavy slides create extraneous load — mental clutter that forces the audience to split attention between reading, listening, and trying not to check their email.
2. Mayer’s Multimedia Principles (2005)
The redundancy principle:
If you speak a sentence out loud, and that sentence is also written on your slide, you’re doubling the load on the verbal channel.
It feels safer for the speaker, but it makes learning worse.
3. The Curse of Knowledge (Camerer, Loewenstein, Weber, 1989)
Experts forget what it feels like not to know.
So they over-explain, over-write, and over-protect themselves with bullet points.
None of these theories are new.
We all know them.
We all quote them.
Yet in the moment — right before a talk — the pull of the old pattern wins.
“This is the way we’ve always done it” is a powerful spell.
🕹️ THE META GAME
When I’m in the audience of one of these talks, I don’t zone out.
I play a quiet game with myself:
How would I make this slide different?
What is the one idea they are trying to say beneath all this text?
If I could only keep six words, which six would survive?
If I removed the slide entirely, what story would remain?
Suddenly I’m not trapped in the talk.
I’m mapping possibilities.
Every flawed slide becomes a creative exercise.
A design challenge.
A chance to practice noticing.
The more you play this game, the more your own slides change.
You begin making decisions with intention instead of habit.
And you start asking questions like:
“Does this slide help, or is it just a security blanket?”
🧰 LESS MESS, MORE MESSAGE
Next time you’re preparing a talk, try playing the meta-game on yourself:
• Start by deleting 70% of your text.
• Keep one idea per slide.
• Speak the nuance; show the essence.
• Let the slide support the story, not compete with it.
And most importantly:
Trust that you — not your bullet points — are the message.
🧭 ASK YOURSELF THIS
Speak soon,
Andy
PS If you’re working on a talk and want help shaping it into something smoother, simpler, and more human, hit reply and tell me what you’re wrestling with. I love this stuff.
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