Almost every interface convention we have assumes a way back. Undo, drafts, a support queue, a chargeback — the reason it is acceptable to make an interface merely good is that being wrong is survivable. Raptor is a self-directed study in what happens to those conventions when it is not: send to the wrong address and the money is gone, with nobody to appeal to. Legibility and restraint stop being taste at that point and start being the safety mechanism, because there is no confirmation email and no reversal behind them.
It also rules out the obvious answer. The standard response to risk is more confirmation, and past a point that makes things worse — people learn the shape of a warning and click through it without reading. So the safety had to come from the layout instead: one signal colour held back for the moment of commitment and kept off every decoration, numbers in fixed tabular columns so a value never moves as it updates, and a commitment screen carrying the amount, what it converts to, and the single control that does it.
