Build In Layers
First layer works alone; each next layer improves it and is not required; stop when the next would go unnoticed.
Formerly Graceful
Progressive JPEG: the coarse whole first, then sharper.
Seen in Steven Champeon and Nick Finck, progressive enhancement, SXSW Interactive, 2003
Try it on your work
Make the thing you're working on in layers. The first layer must work on its own. Each next layer must improve it and must not be required. Stop when the next layer would add nothing someone would notice. Count the layers; that is the depth the thing actually has.
Write the project's description as one sentence that works alone. Add a paragraph that improves it but is not needed. Add a page. Stop when the next addition would not change what a reader does. Publish whichever length the reader has time for.
Design your process so the first hour of any task produces a usable result, the first day a better one, the first week the best. Stop when you can hand over at any of the three points without apology.
How it has been used
Multiple-description coding creates several versions of an image or video stream. Any one description can be decoded at lower but acceptable quality; receiving more descriptions improves the reconstruction, regardless of which arrives first. Unlike a base layer with optional extras, no single stream is the indispensable gatekeeper.
Where it leads
Grouped under Protect what still needs to work