Originally Posted by Jezza
The problem with this forum, and indeed with any internet forum, is that there is an overabundance of opinion and too little in the way of facts to back it up. It's also important to bear in mind that just because something shouldn't happen, doesn't mean it can't happen...
Jezza has made an excellent point, something that we should all keep in mind whenever a discussion focuses on an abnormality, accident, or incident.
There is no doubt that the simplest (the easiest to postulate) theory for any incident or accident is "the crew did something wrong". It's especially easy for all of us who have some knowledge of the subject aircraft to come up with these postulates, because we know how things should be done.
However - many, many accident and incident investigations have revealed that the crew did what they were supposed to do, and the cause of the problem was an uncommon failure elsewhere in the "system" - perhaps a maintenance failure, or a component failure.
Although it is possible that the annunciation system for the cargo door worked as it should have, it is also possible that the annunciation system did not work as it should have - for example, the door was not secure, but this was not annunciated to the crew. Mechanical problems with the latching assembly are also a possibility.
So, let's keep our powder dry and not get too passionate about defending our postulates until the report comes out.