The homepage hero: one sentence or a demo video?

A single sharp sentence respects the two-second attention span. It loads instantly, it's cheap to change, and it forces me to actually know what I'm selling.

But it's abstract — it tells instead of shows, and abstract claims are exactly what people have learned to distrust.

A 30-second demo video does the opposite. It shows the product doing the thing, and watching someone use software is worth a thousand words.

But videos don't autoplay everywhere, they're expensive to remake every time the UI changes, half the visitors scroll past before the first frame, and the ones who do watch are on mute anyway.

I've seen both convert. I've also seen a great video hide a confusing product and a great sentence sell a product nobody understood.

Which one did you choose — and did you ever actually A/B it, or just launch it and hope like I'm about to?