Daily Calorie Calculator — Target, Deficit and Meal Split

Because it assumes maintenance stays constant, and it does not. As you lose weight there is less body to move and to keep warm, so maintenance falls and the same intake becomes a smaller deficit. Real loss flattens into a curve; every linear projection, including this one, is optimistic after the first couple of months.

Faster on the scale, not necessarily faster in fat. Below roughly a 25% deficit most of the loss is fat; beyond it, lean mass losses climb and adherence collapses. Losing 0.5–1% of body weight a week is the range where the loss is mostly what you wanted to lose.

Far less than total intake. The per-meal split here is for planning, not because the body cares when calories arrive. The one genuine exception is protein, which is used somewhat better spread across the day than taken in a single sitting.