Why does paracrine signaling only apply to the nearby cells?

Paracrine signaling elicits rapid responses which only last a short period of time. Thus, to keep the response over a short-distance, paracrine signaling molecules are typically broken down by enzymes or neutralized by adjacent cells. This type of signaling does not occur in long distances throughout the circulatory system, and instead cells communicate via the secretion of chemical messengers, which are ligands that diffuse through space between the cells.