The ability of the body to maintain a state of homeostasis, or physiological equilibrium, is absolutely essential for effective, efficient functionality of all body systems. Hemostasis is the cessation of free blood flow, external to the vascular system, when a vessel wall has been breached.
With the maintenance of homeostasis in mind, it is vital that the body be able to rapidly repair vascular damage, arresting blood flow in the process, while simultaneously maintaining blood in a fluid state within the vascular compartment.