Here is a case of how things can go wrong on an amusement park ride.
Last week on the El Tutuki Splash ride at PortAventura Theme Park in Salou, Catalonia, Spain, a boat derailed and was struck by another boat full of riders (with 2 riders barely getting out of the way of the oncoming boat). Looking at the video, it appears that the front few rows are empty, while the back ones are full of riders. Could this have had to do with the derailment?
According to a park employee who contacted us, no one was reported injured in the mishap.