34→18

Before opening Figma, I went through the information model with Engineering: which fields were genuinely required, which were duplicated, which already existed elsewhere in the system, and which survived only because a decision years earlier had put them there.

Every field the legacy checkout showed by default
18 Stay at checkout What the buyer has to see or confirm to complete this purchase. Delivery address, payment method, order review, invoice confirmation.
7 Reused from the account Already held by the system from a previous order or the company profile. Shown as a confirmation, not a blank field. Tax ID, billing address, saved card.
4 Collected earlier Naturally part of the project brief, where the buyer is describing the packaging anyway. Delivery window, volume, destination city.
3 Deferred to after the order Needed for production, not for authorising payment. Asking for it later removed it from the decision moment. Artwork revision notes, receiving contact.
2 Not collected at all Requirements that existed because of historical decisions, with no current business need behind them.

The goal was never to compress a long desktop form into a smaller screen. It was to reduce how much the buyer had to process before deciding.