Bingo!!!!! We have a winner!!!!!!!!!!!!!!!!!!
What's wrong with the photo is;
In a marine application the double pole main breaker is intended to interrupt both the NEUTRAL/WHITE wire and the BLACK/HOT wire. The main breaker should not be jumpered like that to break only the BLACK/HOT wire.
Red is also an improper color to be used on this particular panel. Red wire denotes 12V DC + or one leg of a 240V AC system. This is a 120V system and as such only BLACK/HOT, WHITE/NEUTRAL and GREEN/SAFETY GROUND are to be used not red. While not the main problem it is one of the many smaller "issues" ....
The other major issue on this boat was that the AC/DC grounding bond tie was non-existent. The GREEN AC safety ground wire is to be tied to the ships DC grounding bus, it was not.
OK now thump chest and give two thumbs up!!
This is what the panel looked like a few hours later. Notice the difference in how it is wired. The top two wires, white and black are the AC input from shore. Out the bottom left of the breaker the white/neutral leads back to the AC neutral bus for distribution and the black/hot feeds the individual branch circuit breakers out the bottom right of the main AC breaker
If your boat is not wired to interrupt both BLACK/HOT and WHITE/NEUTRAL, in a fault, please get this fixed..