I was forced to be the on-duty electrician from time to time, despite not being an ship's electrician. One of the responsibilities for the on-duty electrician was to cut the right circuits in case of a compartment fire. Despite my repeated protests that I didn't know what I was doing and needed additional training, I was forced to be the on-duty electrician. Mind you, there were no other duties I had to perform, just that one, and just in case of a fire, so it's not like my every-day workload was increased. Determined not to get people killed in the event of an emergency, I asked the actual electricians what I should be doing. Turns out, they didn't know either. Their plan was, in case of fire, kill power to the whole ship. I don't think I need to tell you, this is exactly the wrong move to make.
There's an ever-growing number of electronic systems onboard ships, and an ever-shrinking number of sailors to run them. Qualifications are a joke in pretty much every department, at least in the surface fleet. Ships are in a constant state of disrepair, it's not uncommon for 30-50% of the communications equipment to be broken at any given time, parts taking months to receive (mostly due to budget restraints).
Sailors are routinely sleep deprived. It's not uncommon for a sailor to be up by 6AM, work all day, and then be steering the ship from 00:00 to 04:00, with no sleep, followed by maybe 2 hours of sleep before having to work again the next day, and possibly have another watch from 20:00-12:00. Rinse repeat.