drain the swamp when up to one's neck in alligators

(idiomatic) When performing a long and complex task, and when you've gotten utterly immersed in secondary and tertiary unexpected tangential subtasks, it's easy to lose sight of the initial objective. This sort of distraction can be particularly problematic if the all-consuming subtask or sub-subtask is not, after all, particularly vital to the original, primary goal, but ends up sucking up time and resources (out of all proportion to its actual importance) only because it seems so urgent.