We all have control over the work we do. Some more than others, but we all have some. If you find yourself in a position where you can (or must) use your discretion to decide what to work on, how would you decide? Here’s a framework for consideration.
Fits with personal interest. Regardless of the problem you take on, your personal energy is required to establish momentum and maintain progress. If the problem isn’t important to you in a deep, personal way, the project will stall, wither and die. You must have enough personal interest to persist and persevere.