Research indicates that the rivets used were poorer quality than standard, causing an easy fracture path for failure. The research was conducted on many rivet samples retrieved from the shipwreck site. Photomicrographs show the phosphate and sulphate inclusion level in these iron rivets is excessive, leading to a weaker fastening of the ship. You can see this on the scanning electron micrograph, shown below from www.csititanic.com, which shows a long slag inclusion provided a fracture path for this rivet's failure.
This was a policy decision made by managers at Harland and Wolff. The basic motivator is the drive for profits which, in this case, trumped the need for quality. So to avoid the sinking of the Titanic, an executive at Harland and Wolff would have had to say, “no, we cannot meet this schedule and build the three ships safely with materials that are currently available, so we must delay one or two of the ships.” This would have allowed proper materials to be used and would have saved 1520 lives.
This analysis shows that most problems are the cause of policy decisions and ineffective management, not workers like watchmen or riveters. It was an officer who didn’t supply the binoculars, it was an executive who specified the wrong rivets rather than changing the schedule.
The root cause of the Titanic's sinking so quickly was an executive decision far removed from the sinking, both in space and time; As Deming said, “The problem is at the top, management is the problem.”