We run this test on every site we build, usually at a tram stop or in a café. Ten seconds on a phone, then three questions: what is this, who is it for, what would you do next?

If two out of five people get it wrong, the page is not done, however good it looks.

What usually goes wrong

The headline is clever instead of clear. The button says Learn more. The first picture is a mood, not the product. Each of these costs a few seconds, and there are only ten.

The fix is rarely design

It is almost always words. Say what you do in plain language, show the thing itself, and make the next step obvious. Then make it beautiful.