how does a bus, on a track, at a governed constant speed, unable to turn or speed up, kill 3 people between 2015 and 2021?

That's nearly a train.... so how did 3 people get hit by it? And die? 

The govt says it was a lack of fences. 

I can use logic, and figure out that if a fence would prevent people from stepping in front of a bus, then the bus and the fence were not at fault, people jumping in front of a bus were unable to prevent themselves from stepping in front of it. 

https://www.bbc.com/news/articles/c5yq6570je0o.amp