In growth-driven design, every improvement plan starts with a focus metric, and that metric is the top of the hierarchy. Suppose a B2B software company chooses qualified demo requests. A proposed improvement below it should say how it would move that number.
The second level holds suspected obstacles. Each one pairs something the team has observed with its best explanation of how that keeps buyers from requesting a demo. In the example, the sales team reports that prospects keep asking how long setup takes, and session recordings show visitors abandoning the demo form partway through. The pricing page also has a high exit rate, and that number goes on the list with a caution. An exit rate says where people left. It doesn't say why, so it's a reason to look closer before anyone proposes a fix. The other two are still suspicions as well, until a change tests them.
Proposed changes form the third level, and each one sits under the obstacle it's meant to remove. The fourth level is the small set of changes the team has committed to build in the current cycle.
The structure helps when someone brings an idea with nothing above it. In this example, a request to redesign the homepage arrives with no observation behind it. It can stay on the list, and the empty level tells everyone what would move it up: evidence of a buyer problem the redesign would solve.
The method names the focus metric and a repeating cycle of planning, building, learning and sharing what was learned. The four levels are our recommendation for organizing the list inside that cycle. If you're still working out the outcome itself, start with how to create a growth-driven design strategy.