For the onlookers I feel like its one of those "I must be seeing things cause surely not" moments, but by the time reality kicks in its too late. For the workers, its one of those "someone else will do it" moments, but buy the time they realise that none has in fact done it (safety checks) they've already committed to throwing her, even if they noticed in the moment. They preferred the risk of being right (even if it resulted in death) than the risk of being wrong and embarrassed.