In most chat systems, the output disappears into scrollback. If you want to use it later, you copy it out, rename it, store it somewhere else, and lose the causal chain that produced it. That breaks continuity.
Rush keeps the output in the system as an artifact. That artifact can be revised, shared publicly, cited in a meeting, or passed into another workflow. A research report can feed a writing agent. A drafted email can feed a review step. The work becomes modular without becoming fragmented.
This loop is important for distribution too. Shared artifacts are not only outputs; they are evidence. They show what the product did without asking the next person to imagine it.