Six hundred grams is five cups of flour. Measuring that by cup means five separate fillings and five chances to pack the flour differently, which is exactly how a dough ends up stiffer than the recipe intended.
Across the full chart above, this same weight fills 7.14 cups of cocoa powder but only 1.76 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 600 gram weight whenever the recipe depends on an exact ratio between flour and liquid.