not every organ donated is in a suitable condition for a transplant. not every organ is a match for every body. organs are given out based on both time spent on the list and the emergency of the situation. a large amount of families do not know whether or not the dead person wanted to be an organ donor and do not sign off on it. etc etc etc.

if i'm in such a state that doctor's are willing to work less to resuscitate me, well, it's not like i'm going to know that when i'm dead.