Why the advert is thirty seconds

A woman selling handmade bags from her flat in Kuwait asks how long her first video advert should be. Everyone she asks gives the same answer. Thirty seconds.

Nobody can tell her why.

The honest answer is that a choice was made a very long time ago, when airtime on television was sold in fixed blocks and half a minute became a convenient unit to price. That was a reasonable decision for its moment. Then everything grew around it. Scripts were written to fill it. Rate cards were built on it. Editors learned its rhythm. Awards judged work at that length, and young people studied the winners. The unit stopped being a pricing habit and became the shape of an advert.

Now she is filming on a phone, to be watched on a phone, by someone scrolling past with a thumb. Nobody is selling her airtime in blocks. Her bag needs either six seconds or two minutes, depending on what she wants to say. And still the old unit sits there, quietly deciding how her idea will be cut.

This happens to far more than adverts. A small, sensible choice gets made. People build on top of it, because building on what exists is easier than starting again. The more that is built, the more expensive it feels to question the foundation, and so nobody does. What began as one decision becomes a system, and the system is defended because of everything already invested in it, not because it still works.

The trouble is that these systems are invisible from inside. They feel like the way things are.

Until someone new walks in, holding a bag and a phone, and asks a simple question that nobody in the room can answer.