Attribution you can't explain is attribution nobody trusts. When a sale lands on a campaign you didn't expect, you need to see the journey and the rules that produced the result, not a number with no workings.
Why? sits on every sale on the Sales page and on every purchase in a person's journey. It shows the model picked at the top of the page, the lookback window, whether organic touches are ignored and your disregarded sources, then lists every visit by that customer with a label: credited (with its share), counted but given no credit, organic ignored, disregarded, outside the window, or after the sale. When nothing was credited it tells you why: no customer linked, no tracked visits, or every visit outside the window or disregarded.