06/06/2026
The most expensive marketing mistakes I've ever seen weren't made by careless founders. They were made by certain ones.
In the 1990's two researchers, Timur Kuran and Cass Sunstein spent years trying to understand something that bothered them. How does a society become certain about something that turns out to be completely wrong?
What they found was this. It doesn't matter much whether a claim is true. What matters is whether it travels. Whether enough people repeat it that it starts to feel like something everyone already knows.
They called it the Availability Cascade.
And once you see it, you can't unsee it.
A founder I worked with had spent fourteen months convinced he had a traffic problem.
He'd read it in articles.
Heard it on podcasts.
Every agency he spoke to confirmed it.
His competitors were all doing the same thing.
By the time we sat down together, the conclusion felt so obvious he'd stopped examining it.
We looked at his actual numbers.Traffic wasn't the problem.
It had never been the problem.
The people arriving on his website weren't confused about what he sold. They were confused about why they should buy it from him rather than anyone else. More traffic would have accelerated the leak, not fixed it.
He'd spent fourteen months solving the wrong problem with complete confidence.
That's what the Cascade does.
It doesn't feel like being swept along. It feels like thinking. It feels like research. It feels like arriving somewhere through your own careful reasoning.
The certainty is the tell.
Because certainty that forms before the hard questions get asked isn't really certainty.
It's just repetition that forgot where it came from.
I kept seeing this pattern — smart founders, expensive decisions, assumptions nobody had ever thought to question. It's a big part of why I wrote The Agency Advice Trap.
