When creating a quote for a client who has a discount after they purchase a number of the same item works correctly.
The issue is if you quote for a single item (different from the first item but in the same category in the discount matrix) this item also receives the same level of discount even though the quantity being quoted is no where near the threshold to receive any discount.
Every subsequent item that shares the discount category then receives the level of discount even though they are only unit purchases.
Maybe this is a misunderstanding how the discount matrix works but most pricing models only receive discount on a line item that is purchased in large quantities not a sum total of items sharing a discount category.