The DESIGN BACKLOG is an unordered, liquid reservoir of ideas, concepts, and impressions that aren’t being worked on and won’t be worked on soon. Most ideas should go in the design backlog. The design backlog is named after a similar concept from the popular Scrum software development methodology, the product backlog. However, unlike Scrum, it isn’t intended to be part of a formalized development process. It’s an informal tool for retaining inspiration.
Most of the backlog will never be implemented. That’s fine—it means that the parts we do use are probably very good.