What I learned so far: porthole not rated for the depth of the Titanic, apparently no testing done on the balast release mechanisms, screens screwed directly into the carbon fibre hull, flammable interior materials, mixing three materials in pressure vessel (carbon fibre tube, titanium end bulk jeads, transparent port hole).

All more or less untested and uncertified. Throw in the reported comms issues that were common during past operations, a highly inexperienced engineering team, a culture promoting unsafe practices and you get a death trap of a vessel.