Half a bridge doesn’t get anyone halfway across. Some things only count when they’re done.

Effort usually pays in proportion, and then there is a category of thing that pays nothing at all until the very end. Most of a bridge is the same as none of a bridge to somebody standing at the edge of the water. Knowing which kind of task you are holding changes how you treat it, because the nearly finished version of some things is worth exactly zero.

Look at what you are carrying and ask whether partial progress helps anyone. If not, stop opening new ones and put everything into closing the nearest one.