Twice last year on boats I were on.
First time 50 lb braid snapped after 20 minute fight with a tuna, my fault, mono leader too short and I'm assuming the tail hit the braid.
Second time 80 lb braid, tuna within 30 feet from the boat, fish makes one last dive and the line snaps like a 22 going off. First mates fault for not setting the drag properly

drag was way too tight.