We can obsess about guest safety all day everyday, but it is only a matter of time before an incident like this happens. More often that not, problems develop that just can't be detected during routine maintenance.
It could be a manufacturing defect, it could be a maintenance issue, a design flaw, or it could be a poorly thought out "quick fix". I have seen them all, and generally the guilty party stays silent and gets ratted out by the innocent one.
In this case they haven't openly come out and said why it had an abnormal operation. We can speculate all we want but until the evidence is out there its premature. However I am confident that in due time the truth will come out.
In my opinion, the accident's involving Intiman rides have been a series of events that contributed to the accident. You might recall the last Intiman accident on SROS when the train decided to skip block and plow into the one in load/unload.