You’re not the person who identifies all technical projects. Having accountability for the team’s technical investments doesn’t mean that you personally do the research to find potential investments. Instead, you guide these investments by asking questions. What are the current projects, and what surprises or bottlenecks have they uncovered? How is the team thinking about the future of the systems? Which teams are asking for more engineers, and why do they think they need more people? Which teams are slow but don’t want to add more people to improve their throughput? Why are they advocating for this specific project right now? You need to know enough about the work to sniff out misguided efforts and evaluate proposed investments.