Sometimes, the best way to develop a product portfolios is from the bottom up. In other words, you start with a list of individual projects and then use a process of strict evaluation and screening to identify the projects that are most strategically aligned with your company's goals. This approach has a number of advantages. First, it ensures that all of your projects are closely aligned with your company's overall strategy. Second, it allows you to take advantage of economies of scale by grouping together similar projects. Finally, it makes it easier to monitor and manage the progress of your projects, since they are all part of the same portfolio. Ultimately, using a bottom-up approach to developing your product portfolio can help you achieve more consistent results and avoid costly mistakes.