expand_less This concept enables us to take into consideration the biological or organic limits of a given system.
Carrying capacity in general focuses on how much can be held by a container. In an environmental sense, it is how much life can be held in a given container such as a specific ecosystem. Carrying capacity answers the question of what the biological limits might be. Carrying capacity takes into account what flows in, such as birth rate, what flows out, such as rate of death, and various limits to life such as access to water and rate of consumption and recycling of water.
More broadly speaking, carrying capacity points to a relatively stable state of dynamic equilibrium. 
We can often be seduced by growth graphs that have the familiar hockey-stick pattern. These do not account for carrying capacity and the metastable states. Look for where the curve is really an S-curve. Carrying capacity enables us to ask what can increase capacity rather than assuming it is a fixed boundary.