Scoping down work into manageable pull requests (PRs) is essential for developers, as it reduces cognitive load on reviewers, makes testing easier, and facilitates iteration. Small PRs are easier to review, test, and iterate on, reducing the risk of side effects and making it clearer what changes are being made. To scope down work, developers can use tools such as clear expectations of output, branching, labels, feature flags, and tracking what's left. By breaking down large projects into smaller pieces, reviewers can focus on one task at a time, and teams can work more efficiently, with fewer side effects and less mental overhead. Additionally, using the Single Responsibility Principle and limiting the number of changes in each PR can also make review and iteration easier.