For what it's worth, most electrical failures I've seen as an engineer(!) are in cubicle farms. Those plug in interconnections between partitions each contain at least 3 contacts (designed such that any exposed metal contacts are not live). These are little better than the "push and pray" el cheapo outlets. And a load outlet could be connected to the power source via up to about ten such interconnections, to make that 30 contacts (on the hot wire and then another 30 for the current return). One cubicle farm I was in, the installers forgot to, on the little outlet modules, change the phase selection from phase A to B or C on 2/3 of them, and it turned out phase A had all the load.
One company I worked for about ten years ago had so many failures they brought in an EC to run conduit and install 4 inch square boxes for outlets thru out the cubicle farm. We had some smokey interconnections...
