If you're the kind of person who loves a heavy, almost smoky cold brew—like the kind that tastes like roasted nuts and dark chocolate with zero brightness—medium might feel too light. Dark roast cold brew has a cult following for a reason: it delivers that intense, no-nonsense flavor that some people crave daily.

Also, if you're brewing for a crowd that includes folks who prefer a more delicate cup, medium might not be bold enough. Some people want their cold brew to punch them in the face, and medium won't do that.

And if you're buying pre-ground medium roast, you're losing some of the nuance. Whole beans ground fresh make a bigger difference than roast level alone.