Traditionally, large solutions commit early to fixed and detailed specifications for the intent and context. Unfortunately, history has shown that our early specifications are often incomplete or inaccurate. What’s more, the process allows a limited opportunity for feedback and adapting to specification changes. This leads to the late discovery of issues, with no systematic way to improve them. While some requirements and design decisions should be made early (fixed requirements), many can and should be delayed (variable requirements). Economics alone must determine when exploring alternatives should stop and when decisions should become fixed. In the spirit of assume variability and preserve options, SAFe allows everything—the Solution, its Intent, and its Context—to vary during development.
At scale, creating a single source of truth for all requirements and design decisions becomes critical for aligning and coordinating all ARTs and their teams. The solution intent reduces the risk of misaligned work. It aids planning and helps ensure the delivered solution has the proper fit for use, fit for purpose, and will yield quality outcomes. SAFe’s Economic Framework also enables localized decisions on serviceability, manufacturability, unit costs, and other critical decisions, which accelerates decision-making and reduces delays. Moreover, modeling, simulation, and low-fidelity prototypes allow teams to prove out decisions and obtain feedback quicker as they iterate across multiple potential solutions in a cost-efficient manner.
Apply multiple planning horizons
Development plans for large solutions have often been defined by a fixed, hierarchical schedule that breaks down work and attempts to coordinate teams by early task assignment. In practice, these detailed schedules quickly diverged due to many circumstances—technical discoveries, gaps in specifications, and new understanding from customers. The ‘plan was not the actual,’ and rigid, detailed, long-range plans hindered the ability to adjust. In contrast, ARTs and teams use Backlogs and Roadmaps to manage work and forecast the current understanding of the schedule. As new knowledge becomes available, items can be added, changed, removed, and reprioritized to ensure delivery of the most value per increment.
SAFe’s Roadmap describes the need for multiple planning horizons. The Solution Roadmap provides a multi-year product vision while the PI Roadmap estimates nearer-term capabilities and milestones. As shown in Figure 5, Solution Trains are responsible for the long-term Vision (2-5 years) and near-term Roadmap (3-4 PIs) that their ARTs and teams use to define their Backlogs and plan their PI Roadmaps. The Vision provides the broadest context—the aspirational purpose that creates the boundaries and framework for planning.