blood always clots when taken out of body.. my own nosebleed this morning a got when I woke up was starting to clot before I got a kleenex for a it... And I have delayed clotting of a genetic condition... takes a long time for the bleeding to stop and I have bleed seriously many times in my life.

if blood is drawn for a lab test where clotting would be a problem there are anticoagulants added to the tube. This is my real life observation from nursing and biological education.

your blood starts to clot with death in minutes ...If there was education on this.. these stories would be found by most to be bullshit.