Last night I'm the first to board on a RDU/MIA flight and when I try to board the system flashes red and the GA tells me to hold on. Then the Captain comes up says something to the GA, GA asked like 5 minutes and Captain says probably not. GA won't say what the pilot had said. So we just stand there for over 30 minute. Finally when pressed the GA said she can't reveal the reason for the delay because she isn't allowed to. Turns out the fueler lost control of the fuel nozzle sending fuel all over the tarmac and plane which took 90 minutes to clean up. As far as the topic at hand FAs make a calculated risk a flight will be cancelled. Why is that their problem?