> You don't need tons of complexity. You can make any system infinitely complex, but this is a choice. A billing system with -- and I quote -- "160000 combinati

> You don't need tons of complexity. You can make any system infinitely complex, but this is a choice. A billing system with -- and I quote -- "160000 combinations" is too complicated for customer support to understand, too complicated to explain to consumers, and will inevitably result in people getting billed incorrectly. I think the author is just referring to a configurable promo's and deals type of engine, which is pretty common. It just gives the business the ability to configure as opposed to hard code. For example, maybe the business wants to run a buy one get one free type promotion, this can just be configured into a generalized engine that allows for qty hurdles (or amount hurdles) that trigger some discount on some set of items.