I ran a stand at ISPO, once the largest sports trade show in the world. I controlled everything on that floor: the lighting, the sound, the mood, the story I told about the product. Customers walked away convinced.

A few months later I sat in a courtroom on charges of misleading advertising. None of that control was mine there. I have not felt a starker shift between two rooms.

At the trade show a claim was enough. I said the product worked, and people believed me. In court the judge asked for evidence.

For years I had built the pitch on testimonials, celebrity endorsements and what we called a balance test. The pieces worked together on the show floor and reinforced each other every time. None of it counted in the courtroom. The judge asked for studies: double-blind, controlled and reproducible. I had none.

I remember the emptiness of that moment. I had spent years on the product and believed in it myself. Thousands of people had told me it worked. I had taken that as substance, because everyone around me confirmed the effect. None of it counted as evidence in court.

I am leaving out the trial itself here: its details, the people involved, the outcome and the naivety that led me there. That is a separate story, for another time. I was also aware of my guilt. What stayed with me afterwards is a different question: in which of these two worlds do we actually spend our days?

Almost entirely in the first one. We buy because something feels right, or because a seller has stirred the right want in us. We trust people who sound convincing and believe stories that are told well. Testimonials and a gut sense that something must be true because everyone around us says so: this is the world most of our decisions run on, and it runs smoothly for as long as nobody asks for proof.

The courtroom is the one room I know where storytelling stops working. Nobody could tell the judge that customers felt it, or that thousands of people could not be wrong. The room asked for something harder: facts that are true whether or not anyone believes them.

What unsettled me most was watching how thin the ground under my own decisions had been.

Since then I check things differently. When somebody tells me a story to sell me something, I ask myself a simple question: would this hold up in front of a judge? It works as a plain filter. A judge asks what the facts are, not how much customers love a product, particularly customers I had misled, as I recognised afterwards.

Most decisions do not need a courtroom. I have kept the habit anyway, and I ask myself what remains once the story is stripped away and only the facts are left. Usually less than I would like. The excitement drops and a plainer kind of clarity takes its place. Then, before long, I miss being sold something.