When a B2B customer makes an order, and it is so big it breaks a threshold, the whole order is discounted!
The threshold could be based on price (e.g. orders over £500 are 5% off) or it could be on item quantity in a certain product or product category (buy 5x of one product, get 5% off that product line).
Some companies I know are doing this manually after they receive the orders, but before finalising them. That would really save a lot of time and increase the effectiveness of the B2B platform if those people didn’t have to do that! It could easily lead to sales increases for customers who haven’t thought to do this yet as well.