Blood clotting is a complex process involving
several factors and several steps in the chain of reactions that produce a
There are several reasons for this complexity:
Each reaction amplifies the next one in the chain, to produce a
faster, stronger effect. This type of chain reaction is known as a cascade
It is possible to "fine tune" each reaction in the series, making
the final result a targeted response.
If the reactions were simple, or involved only a few steps, it would
be more likely that the blood would clot easily inside the blood
vessels, instead of just at the site of a wound.