If I am correct thats a couple of years old, every year they hold an airshow on the beachfront in the UK and that was the Harrier display aircraft.
Can't recall the venue but that film looks very familiar.
Cause was pilot error unfortunately, moved the wrong control at the wrong time
Have not seen the pilot for quite a while, I believe he is now piloting a desk.
Btw they use water injection for added thrust whilst in the hover. however that much water was more than required

As for worst operational record in the gulf, well think about it.
Sand kicks up from nozzles and guess what gets fed straight back into the intakes, wrong plane for a desert environment.