PERSONA: 35, DAILY USER
- Finds Continue in under a second. Ignores the copy above it.
- Autofills card. Never reads the error text.
- Completes in 41 seconds.
A 68-year-old agent finds it. An actual 68-year-old confirms it.
Same screen. Two people. Two completely different products.
You built this. You know where the button is. You have never once looked for it. Everyone on your team has the same blindness, and your AI has a worse version of it, because it read the code that put the button there.
The same checkout, annotated twice
PERSONA: 68, FIRST TIME
- Reads the paragraph above the button. It does not say what happens next.
- Taps the low-contrast link twice. Nothing appears to happen.
- Card error clears the form. Starts again. Stops.
Neither column is a bug report in the usual sense. Nothing threw an exception. The tests passed. One person finished and one did not, on the same build, on the same day.
What the human tester added
The agent flagged the cleared form as a flow break. The human tester of that age said something the agent could not: she assumed the payment had gone through and did not want to try again in case she was charged twice. That sentence is why the fix is a confirmation state, not a form patch.
Pick the age group your product actually serves. That choice changes the report more than any other setting.
Your AI wrote the code. Nobody checked if anyone can use it.
Cotesty runs your app through AI personas matched to your real users' age group, then real human testers of that age, and hands you one report of everything broken.
Every statistic on this page links to its primary source. That is the same standard we hold our reports to.