In logistic growth, the term (K-N)/K represents:
The factor (K - N)/K, equivalent to 1 - N/K, represents the unfilled fraction of carrying capacity and is often interpreted as the fraction of growth opportunity or resources still available. It equals nearly one at low density, falls as N increases, and reaches zero at N = K, thereby scaling the unrestricted rate rN. Logistic predictions depend on assumptions that managers should not overlook. Carrying capacity changes with habitat and climate, and removing individuals may alter age structure, social organization, or genetic diversity. Thus an algebraic optimum is a benchmark, not a guarantee
Ref: Ecology: Concepts and Applications, Molles, 9th Ed., Ch. 11