Four hundred grams is the scale of a double batch: two loaf tins of cake, a large cookie tray, or the flour in a two-loaf bread dough. At this size, small per-cup errors have compounded into something visible.
Across the full chart above, this same weight fills 4.76 cups of cocoa powder but only 1.18 cups of honey. Cocoa is the lightest ingredient here and honey the heaviest, and that spread is the whole reason the ingredient has to be named.
Keep the original 400 gram weight whenever the recipe depends on an exact ratio between flour and liquid.