There’s a place near the equator where the prevailing winds are generally calm. If your ship only has sails, finding yourself in the Doldrums could mean days or even weeks just drifting aimlessly.
Which is why you might have heard of the Doldrums. Personally, I most often use the term to describe the two hours after a big lunch when you just sit at your desk reflecting on poor life choices, but wait. What was I talking about?
Damnit. There’s a metaphor here about how you can’t just wait for the wind. You need an engine to power through the Doldrums, maybe something you really care about to fuel that engine.
I’d polish said metaphor, but I’m kinda paddling my way though these things lately.